My favorite pack for around the city is:

REI Flash 18 Pack $34 - super light rucksack, fun colors (but also stealthy black), I carry a 32 oz water bottle inside mine

http://www.rei.com/product/827110/rei-flash-18-pack


They recently had the older model on sale for $20 but these new ones are still a deal at $34. I abuse mine and they hold up great.


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