I bought some headphones this week (Sennheiser HD600s) so that I can continue to work during the period where my girls are getting to sleep. To be honest I didn't expect much - I figured I could use them for composing, but probably not getting the mix right or anything.
Tried them out tonight, and was utterly bowled over. The bass was just incredible, to the extent that I was genuinely convinced I was feeling it through the floor, and had to check that the sound wasn't still coming out of my subwoofer as well. If anything, other than the lack of a real stereo image, I feel I'm hearing the mix better than on my monitors.
Sorry about the OT; I just had to share my excitement. Wish I'd got headphones years ago.