I was thinking I could replace my seat bag (tubular, CO2, keys, cash) with a Bottle Holder (attached to the seat post) IF I could come up with a decent solution to still carry these items. I could stuff them in a jersey pocket or a CamelPak, but I'm trying to keep my back cool (it's warm finally) and those unused bottle cage mounts look appealing. I was wondering if anyone knew of a decent bottle cage mounting holder for small items like the ones I need to carry.