I average 45 minutes each way which is about right. Nice days I can lengthen it out on the way home, but when I have to get in early it's not too big of a drag--plus it's just as fast as the train + walk to work, and I think driving + finding a parking spot would probably take just about as long/longer, I passed a motorcycle near the house this morning and he didn't catch up to me until I was 3/4 of the way to work.....

I don't think I'd ever go much more than 15 miles each way (it's 11-12 depending on the route now), but that's largely because I don't want to live way out in the 'burbs and I'd rather sacrifice some housing space for proximity to job/entertainment/fun.