I have this pack and it has more than enough storage space for a day trip.
Brad's Deals Editor Candace,
This Eddie Bauer Stowaway Packable 20-Liter Daypack drops from $30 to $15 at EddieBauer.com. Shipping adds $7.99, or it's free on orders over $99. That's 50% off the original price and ties with the lowest sale price we've seen so far this year, although free shipping was available previously. It is available in seven color choices, plus it has a water-repellent finish and lightly padded shoulder straps. Sales tax is charged in most states.