Pints Barn hosts a run every Thursday. There's lots of people (~200) and it's only 3 miles.
Just meet at the Pints Barn in Tumwater near Tumwater Falls. Stay afterwards for a cold brew or a hamburger while sitting out on their patio. See you there!
This event is with the Pints' Pavement Pounders Running Club: http://www.facebook.com/pintsrun
If you've never run with P3, come early because you'll need to sign a waiver. Actually, it's good advice to come early because parking can be crazy, or car pool! Do not park in an illegal spot as enforcement is strict around Pints Barn.
This is not a normal meetup in the sense that most of the people at the run know nothing about meetup. We post it on meetup since a lot of meetup runners attend this event. To get to know the group first, check out the smaller runs on other days. But don't let this deter you from coming out anyway - it's a lot of fun taking over Tumwater with 200 runners!