Have you ever been to a "Wear 'Em Out" type event? ("Wear 'Em Out" is at the Northgate Community Center. At some point, I saw a list of the same type activity at other community centers, but I can't find it now.) It may be even more frustrating to be surrounded by hyper toddlers than to just have the one at home, but I thought I'd mention it...

Oh wait, here's a list: http://www.cityofseattle.net/parks/Children/play.htm Although they aren't clear if you need any kind of registration or if there's a fee.