I have completed my 12v power supply for small accessories. I use it to power my GPS.

I picked up a weatherproof 12v powerpoint (cig lighter socket) at walmart. It has a flat side and tywraped under the center of the handle bars. It strapped on easily,and I rode with it a couple of days before I wired it in, to ensure there would be no issues with the location.

To wire it up I used crimp connectors, a buss fuse holder (the cheap round style), #18 stranded auto wire, shrink wrap and liquid tape.

1) Ran 2 wires from the handle bars under the tank and under the seat. The - wire will drop down to the - terminal of the battery so left lots of extra and cut. The + wire will drop down into the tool storage compartment so again left lots of extra and cut.

2) Used crimp on butt connectors to connect the 2 wires from the  power point to the 2 wires I just ran. I have a proper crimper to do this. I have found that this works the best to ensure a proper connection that doesn't pull apart. Be sure to slide  the shrink wrap on the wires before  you crimp the connections.  
Once crimped I  coated the connections with liquid tape. Just enough to seal them up. Once that had set I slid up the shrink wrap, heated it and voila, a weatherproof connection.

4) I used a multi meter to figure out which wire sb the +. The centre point on the 12v supply is + so I made sure the wire connected to this dropped to the tool storage area which is the + side of the battery.

3) Disconnect the battery. Cut the - wire to length, I left a generous loop under the seat just incase. Crimp on a terminal to the - Wire. I also used liqiud tape & shrink wrap in this.

4) Crimp on a terminal connector to one side of the buss fuse holder. I chose the side that doesn't expose any live wiring when its pulled apart. Seal & shrink wrap the connection
Butt connect the + wire to the remaining side of the fuse holder. Seal & shrink wrap.

Hook up the - terminal and - wire connector  up to the - side of the battery.

Hook up the + terminal & fuse holder to the + side of the battery. Put a fuse in the fuse holder.

Everything worked ok so I finished up tywraping the wires to existing stuff and put all the parts back o the bike.

It's been 1 week, 600 miles and 1 horendus hail storm ( Me and the bike got drenched) and no issues.

I wonder if the bike can provide eought power for aheated vest?

Here's a lik to some pics of the install:

http://www.bikepics.com/members/mkram69/p2/

I have a 5 amp fuse in it now. I doubt the bike will be able to power up anything much over this. The fuse is there mostly to ensure nothing else frys if theres a short circuit. I'd rather replace a fuse rather than some funky electronic ignition module.

Thanks for the info Thumperclone. A few recent posts have shown guys with issues when adding lights so I thought there might a low output limit issue. I'll keep the fuse undersized, until I find the need to add any accessories.

How do you find the  halogen lites? Do they help at nite and increase you visibility during the day? Something like them will probably be on my short list.