I mentioned these in another thread, but I like the Performance Ultras. They're short and have a elastic, molded chamois like much more expensive shorts but are very reasonably priced. You can pick up two pairs for less than the price of one pair of some shorts, and I find them to be the most comfy I've worn. Check out my review on www.girlbike.com and you can see how short they are on me (I'm 5'2"). I would wear them for a century and plan to come May!

Good luck,
Emily