Every day as a matter o fact! I have 2, small JR Manta for buzzing around and a Cortech 14 L which I use for the daily commute. I hate carrying a backpack. I don't like the feeling of it on while riding (restricts movement, constant distraction and it was hot).
When the time is right and the cash is available, I'll be investing in one of those Third Wheel Trailers for some serious travel!