I ride a bike.  Ok, maybe not as much as I should.  But I do.  On commutes, errands, casual/leisure rides I really like the Timbuk2 Classic.  The Small hauls a change of clothes, lunch, emergency supplies, a camera and if I'm pretty creative, I have a little wiggle room for other stuff.  The Classic is a smile machine for 2 big reasons.

1) the rugged outer fabric and the waterproof liner in the inside.
2) the awesome side-cam shoulder strap that helps keep the bag from swaying like a pendulum if loaded with um, substantial enthusiasm.

If you're even thinking about a Timbuk2, you're on the right path.  These things will last forever.

At first thought, you'd think they might be overkill for a quick trip to the corner store, but they are a perfect reminder NOT to fire up the dinosaur burner.  So now I have multi-tasked mine for messenger bag, camera bag, errand bag, grocery bag, farmers' market bag, overnight bag, commute bag...

<a data-hook="product-link-linked" class="a-link-normal" href="/Timbuk2-Classic-Messenger-Bag/dp/B003386CVC/ref=cm_cr_arp_d_rvw_txt?ie=UTF8">Timbuk2 Classic Messenger Bag</a>