For some runners, it’s all about the swag; you’ll see Monster Dash zip-up tops all over town for months afterward. But the real return on your (not insignificant) investment in this annual race from the Cathedral to the river and downtown St. Paul is how much sheer fun it all is. For all but the die-hards, this is the last big event of the season before winter kicks in (it’s on Oct. 31 this year), and there’s a Halloween costume party atmosphere from the start to the finish line. The bonus: It’s nearly all downhill, so your time is almost guaranteed to make you look good, even if your costume doesn’t.