I tried reverse-lens macro for the first time because the adaptor + extension tubes were relatively inexpensive, and I love my 100mm f2.8L lens so I wanted to try something new.
It took a fair amount of practice, and a fair amount of patience, but I have gotten some wonderful results. I used the Canon "Nifty" 50mm f1.8, a set of cheap extension tubes, and a flash with a little diffuser on it, and have gotten some pretty (in my opinion) awesome results. The IQ is what it is with the 50mm lens, but the good news is you always have the freedom to get a better lens option (the wider the lens is normally, the more magnified it is when it's reversed.) and or a more magnified image.
I'd say if you are interested in Macro photography at all, this is really a no-brainer. All the different parts you'll need, Reverse-Lens Adaptor, Extension Tubes, and Lens to play around with, can be had off of Amazon for very reasonable prices by photography standards.
Check out the work of Thomas Shahan, a Spider portraiture specialist who works in the Reverse-Lens macro medium...http://www.thomasshahan.com/#photos
He makes some really beautiful and interesting images and has served as a huge inspiration to me.
And here is a flickr gallery of images that I have captured with this set up on my Canon 7D...http://www.flickr.com/photos/17873203@N03/sets/72157633194724521/
I've got some way to go to achieve what Mr. Shahan has, but I'm looking forward to trying.