If you're not spending this weekend SIFFing or Sasquatching or otherwise out of town for the three-day weekend, there's plenty of live music for those who spend the holiday in Seattle. Tonight, instrumental Chicago rockers Pelican play the Showbox SoDo. No need to stay for headliners Thrice, just these guys: Or if you like your rock with more synthesizers, head to Nectar for the Presets.......