Just discovered this thread -- started in 2002 and now has over 1100 messages; is that a record?!!
I started cyclocommuting (trying to coin a word here -- I hate "commute by bike") two weeks ago after I got an awesome full-size commuter pannier (i.e. like a garment bag that drapes over the rack) at a used swap for $23. Since then, I've only been able to cyclocommute one day a week, but this week I'm aiming for 2 or 3. Mostly it's a logistics issue -- I can't do it if I have somewhere to be after work.
The first two times went really well, but today was pretty hard for some reason; can't tell if I was just sluggish (I only got 6 hours of sleep as opposed to my usual 7) or if my new fenders were rubbing slightly against my tires, or if my new front tire needs to be broken in, or what...but it just felt like I was phoning it in. I guess that just happens sometimes, but hopefully I'll have a better ride home and will try tacking on a few extra miles just to get a good full ride in.