My normal commuter is a full size truck. I try to maximize my mpgs but it's still tough on gas. However I didn't feel too bad about it because I spent much of my time commuting on a motorcycle, my ZX6R.
Then it got stolen (April 2009).
I had no budget for a bike, so I bought an R1 that was really cheap because it was broken and I had a bunch of spare parts already. When I finally got it running, something new broke nearly every time it rode it and it was turning into a money pit. So I sold it.
And bought a Ninja 650R in excellent shape for the same low price as I sold my beater R1.
Not my bike, but it looks exactly like this:
Reliable and EFI. Slower and not as nimble as my old bikes, but still very fun to ride. I'm happy. First tank: 52mpg.
I probably won't do a whole lot to it, but I do plan on changing out the sprockets to get the revs down.