If I may chime in, I recently read this post while in search of a way to reset my service reminder on my 2006 Land Rover LR3. I, like most people on this list, perform most of my basic maintenance and other light work on my vehicles, and the Rover is no exception (even though I've got an old '71 Series IIA that is a little more fun to work on).
However, it always frustrated me that there was no "manual" way to reset the service light indicator. So after reading the above post by brettmess24, I hopped on blackbox-solutions.com and ordered up one of the Can-Mate SRT's (total cost with shipping and the UK-to-US price conversion was around $150).
I ordered it Sunday, and received it in my hand today. Honestly this thing couldn't be easier to use...you turn the dial to select the reminder time option, plug it in, and it's done. No more annoying reminder display everytime I start the vehicle. I always like to give real-time feedback since these forums are so valuable to providing information I frequently need, so if anyone is looking for a testimonial this should do it. Only wish I had the $$$ for their Faultmate that someone mentioned above, but between my OBDII scanner and the Can-Mate that should be able to handle the basics.