What the heck is "real-time asset management"? Isn't that something my stock broker does? Oh wait, I fired my stock broker. No, this is something different.

Think of it as LoJack for your boat. Imagine a device that combines GPS technology with some form of low-power RF communication to let you know where your boat is, all the time – even if your kids, friends or some uninvited guests decide to take it for a spin.

Sure, it's "Big Brother" – but you get to be the big brother.

Vessel trackers have become small enough, and inexpensive enough in some cases, that a system can be had for virtually any boat, even a PWC or dinghy.

PARADOX MARINEBesides providing status and location reports, Nav-Tracker packages them so they can be displayed in Google Earth.This overview is not exhaustive – there are many solutions on the market – but it should help you better understand the extremely broad range of features, coverage and range options and prices you'll encounter as you shop.

PARADOX MARINE'S NAV-TRACKER

One of the most-expensive systems is also one of the best. Wireless boat-security system supplier Paradox Marine produces the Nav-Tracker, which uses Inmarsat's satellite network to provide tracking and monitoring anywhere in the world. The system monitors a boat's location and, if it escapes its predefined "geo-fence," notifies up to 10 people by e-mail or text message every 15 minutes with the vessel's latitude and longitude, speed and heading.

Nav-Tracker.com is Paradox's new tracking Web site, which incorporates Google Earth to display a trace (breadcrumb trail) to show precisely where a vessel has been, anywhere in the world. Since Nav-Tracker uses a two-way satellite connection, you can configure the system right from the Web site.

PARADOX MARINENav-Tracker consists of a central unit below deck and a small Inmarsat/GPS antenna with a clear view of the sky.

Nav-Tracker options include fully configurable and schedulable status reports, as well as alarm notification reports for a wide range of security sensors, bilge-pump sensors, and the like. With the Web-based interface, users can arm/disarm the system, adjust the geo-fence radius and reporting intervals, ping the vessel at any time for current position, and configure notification recipients.

You can even select which alerts go to which users, and give different users different levels of authority for the account, from view-only options to complete control.

Here's the text of an actual Nav-Tracker message. This is what you would receive via e-mail, or as a text message on your phone:

User: Paradox Marine
Asset: M/Y Island Time
Fleet: ETI
DateTime: 2009-03-25 15:06:28 (EDT)
Event: Geo-fence breached;
Location: 26.05767,-80.13033 (0.75 mi NE of Hollywood,FL(33019))
Speed/heading: 9.2 Knots, 144 Deg
Google Earth Map: [KML]

The basic Nav-Tracker system costs about $1,000, and service plans start at $1 a day. Nav-Tracker 2.0, which starts at $1,500, includes the ability to add security and monitoring sensors, as well as local control of the unit. Nav-Tracker is one component of Paradox's extremely comprehensive line of vessel security and fleet-management products.

BLACKLINEBlackLine GPS's Harpoon is compact.  BLACKLINE GPS HARPOON

This is a smaller, bare-bones unit that does essentially the same thing as Nav-Tracker, except that it uses the cellular network instead of satellites. It features a Web interface for configuring, tracking and mapping. Obviously, it will only work in coastal waters with good cellular coverage. For some smaller vessels, though, this coverage will be more than adequate.

The Harpoon unit features a built-in motion sensor. For smaller boats on trailers, this can alert you that someone is moving around on the boat, even if the boat isn't moving. For boats stored afloat, you disable this sensor to prevent false alarms, relying instead on location changes indicated by GPS.

The costs is about $350, with a monthly subscription plan of approximately $20. One cool feature: a wireless key fob. When you get to the boat, the Harpoon disarms itself. When you leave the boat, the system arms itself again, with no action on your part. Easy!

BLACKLINEBlackLine's Web site allows you to configure and monitor the Harpoon units, and it displays your vessel's location with Google's online mapping.

CHEAPER OPTIONS

There are some cheaper options available, including non-marine units and some home-brewed solutions.

For example, there are a large number of car-tracking systems out there. The Zoombak is one of them. It isn't a marine product, and perhaps that explains why it's only $200. But essentially, this product does the same thing as the others, again relying on the cellular network to communicate, and using a Web-based interface to display the location of your car . . . er, sorry . . . "boat." Service plans run $15 a month.

If you're willing to risk a bit in the area of reliability and able to do some work yourself, you might be able to accomplish basic, bare-bones vessel tracking for less money. Be warned that all these home-brewed, do-it-yourself solutions require a bit more effort, time and energy. Also, you can't expect to resolve any problems by placing a call to tech support.

INSTAMAPPERInstaMapper is a free online service that maps a real-time cookie-crumb trail using a GPS-enabled cell phone.INSTAMAPPER AND GPS PHONE

This is an extremely inexpensive option, using any GPS-enabled cell phone and the InstaMapper free online mapping service. The InstaMapper Web site includes complete step-by-step instructions. Suffice it to say that with a $40 phone, an unlimited data plan (35 cents a day), a recharger adapter to power it and a free InstaMapper account, you'll always know where your boat is.

As long as you set it up right, and nothing goes wrong – that includes making sure nobody disconnects it – the system should work well.

APRS OVER HAM RADIO

OK, you really need to love to fiddle with gadgets to make this APRS option work. But, you could end up with much better range than systems that rely on cellular networks (though not as good as satellite-based systems). Steve Roberts, the original over-gadgeted technomad, is the fellow who clued us in to this. Navagear first addressed this option in a recent article.

SPOT SATELLITE MESSENGER

Remember the SPOT Satellite Messenger? It's not really a Personal Locator Beacon (PLB); those devices are like a personal EPIRB, intended to be triggered only in the event of an emergency. Instead, SPOT is a tracker that provides periodic position reports via satellite, from anywhere in the world. And it's packed into a small, rugged package, at a reasonable price. It's intended for outdoor recreation enthusiasts in all kinds of environments.

But hey, could SPOT be used to track down a lost boat?

I suspect that SPOT could serve as a vessel tracker, anywhere in the world, if you could figure out a way to power it without relying on the internal batteries. You would need to open up the battery compartment and modify the unit to accept power from the boat's batteries, stepping down the voltage appropriately.

Nope, I've never done this, but it should be possible. One huge caveat, of course: You would certainly void the unit's warranty by tampering with the power supply. A SPOT typically sells for about $150, and a one-year service plan with the tracking option is $150.