The crowd at Flex has been more mainstream as of late, but the vibe there is still edgy enough to call it underground. The sound system is unrivaled, the cover price usually reasonable, and dress code non-existent. The DJ line-up has local heroes alongside international names, and live acts are also on the menu. "Beat it" on Thursday (the night for drum & bass) and "London Calling" (underground rock) on Friday are among the most popular nights. In summer, boisterous partygoers inhabit the picnic tables lining the canal where a snack stand is ready with fries and hot dogs. Check website for DJs and acts.