Lightweight folding backpack?

Montbell makes a few small and very light weight backpacks — including some that can be folded up real small and stashed away. So does Ricksteve.com — for travel use.

off the top of my head, here are some ultralight packs that fold into themselves. Enjoy!
REI Zip Travel Daypack
http://www.rei.com/product/754685

Sea To Summit Ultra-Sil Packable Day Pack (probably the lightest commericial available pack in this category)
http://www.rei.com/product/799600?preferredSku=7996000027&cm_mmc=cse_froogle-_-datafeed-_-product-_-7996000027&mr:trackingCode=C4B0A1E3-F810-DF11-BAE3-0019B9C043EB&mr:referralID=NA

REI Flash 18 (I lied, this one doesnt fold into itself)
http://www.rei.com/product/778466

Patagonia Travel pack
http://www.patagonia.com/web/us/product/patagonia-lightweight-travel-pack-backpack?p=48816-0-803&src=perfdf&slc=en_US&sct=US&src=pfmxdf&src=gps&mr:trackingCode=C1697444-2702-DF11-BAE3-0019B9C043EB&mr:referralID=NA

The REI zip travel pack looks pretty kick Ass for the weight, and you can't beat the price. Surprised we haven't seen much word on it.

How about the North Face Flyweight Rucksack. I now use it as a suitcase, and dump my clothes in the hotel dresser, when I go hiking while on business trips. It can be found for under $50. 32L, weighs 11.8 ounces, and easily fits in airplane overheads and under seats.

Here are some pictures.

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=19032&skip_to_post=150197

I have been using this for a year now and it really holds up. It is not one of my go to packs. But I often use it on day hikes.

thanks for the quick answers! :)

when looking at those packs I came across some exped backpacks that look quite interesting, for example the exped pocket pack 25 with 260g

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