I have some NEW DIY pack pouches designed to slide on side compression straps to add easy access to gear. These were designed off the ULA Circuit as a base, but they're pretty universal.

Two larger side pockets that could fit a solo tent, rain gear, or a down jacket.(10" X 6") 4 loop attachment points, slide top two onto upper compression strap. Weights are 18.5 grams and 15.2 grams on those looking for $10 shipped each.

One small pocket that fits my rain shell jacket, beanie, first aid etc. (5" X 6") Weight is 5.9 grams looking for $7 on it. It slides on a side compression strap. No attachment loops.

Sunglasses Pocket/Sleeve or iPhone 4,5 pocket for backpack shoulder strap (7" X 2.5"). Weight is 4 grams. Top and bottom attachment loops. $7 each shipped