Hey jp, I swear I'm not stalking you . I don't know if folks from other areas get the climate and altitude stuff we have to deal with in CO. It's pretty hard to bring the right clothes in your pockets if you are doing a long ride that goes from 5000-10,000 feet, with temperature variations possibly from 90 in the plains to 40 and hailing/snowing/raining in the mountains, and then you have to descend in that weather. So, yeah, some of us resort to fredliness in order to carry enough clothes to not freeze. Sure, lots of roadies just deal with the pocket space issue, but it's worth having options.

THere are a few light weight seatpost clip on packs. Detours used to make a great one, but it's not on their web site right now. It was called the Hightail UL (UL for Ultra Light). There are a few version of it - UL, ULP, EXP, etc.

Here's one site that has it
http://schwabcycles.com/product/deto...ag-54845-1.htm

Probably not that different from the Topeak one linked above. Any of those seatpost clamp-on things shouldn't be used with a carbon seatpost, unfortunately.

I prefer this pack over the leather & canvas ones, not just for style (I'm not a retro-style-lover) but also because they are much much lighter weight.

You're going to find it's worth investing in legwarmers, armwarmers and a lightweight jacket, though. Don't waste your time with cheap stuff, buy good stuff once. It doesn't have to be Assos or Castelli, but it shouldn't be Performance brand either.