I want to at least attempt commuting this year to see if I like it - only 1-2 days a week. I do not want to rush out and purchase a dedicated commuter bike however...but neither do I want to attach a permanent rack to my beloved Gunnar. If I decide I like it and see that I will continue commuting I will put something appropriate in layaway - I actually already have my eyes on something but I am not about to get ahead of myself on this (a Scott with belt drive + disc brakes). I just sold a lovely bike that didn't get ridden...

I've seen on occasion bikes around town that appear to have removable racks attached to the seat post. I've right at 2.5 inches of seat post showing... With my neck injury last fall I don't need to carry more than hydration on my back...
Does anyone have experience with these or something similar? The store I linked to has their annual sale event this weekend...