I have a p7 rechargeable also but for what you want I strongly recommend you look at the two watt (500 lumen) Blaze two watt light from Planet Bike. It sells for around fifty bucks and uses two AAs. It is really bright even in daylight and is a lot smaller lighter and less clunky on your handlebars because it was designed for bikes. I have had a guy on a bike flag me down to see what my light was because it was so bright at half a mile away. Despite my brighter P7 light this is what I prefer for touring. The beam is designed for biking and the double AAs mean that when they run down on a tour I can get replacements anywhere and not have to carry a charger. Excellent light! Outstanding brightness with cheap readily available batteries and small and lightweight.

http://ecom1.planetbike.com/planetbike/media/3045.jpg

Researching all of the P7 lights on DX and looking at all of the battery options and all of the charger problems and all of the comments about how to fix the switches and heating problems and quality issues and it just goes on and on. The little planet bike light is simple because you just buy one model and drop in a couple of AAs and it works perfect forever. Batteries last over twelve hours on brightest too. If you do not want to research and become an expert on deal extreme lights and spend hours comparing and gambling that the one you pick won't be defective then just grab the blaze. I own both and honestly the little blaze is the way to go. It is bright enough to actually see the road ahead too, not just for being seen. Not as bright as a P7 but for occasional use when you stayed at a friends past dark (like the original post said). One last thing is that these nice p7 lights are tempting to steal so you cannot leave it on your bike. The blaze does not look like something anyone would want to steal. You just leave the blaze on your bike all the time and the day you stay too late it is there ready to go to work. The day you need your p7, it will be at home somewhere doing you no good at all because you cannot leave it on the bike.