The 2014 RVA Hackathon is a 10-hour challenge from 8am to 10pm on Saturday April 12th, at the Lewis Ginter Botanical Garden. Attendees can work independently or as a team, without restrictions -- build anything you like, free of langugage or platform restrictions.
You can find out more about the event at rvahackathon.com (and check out last year's event at 2013.rvahackathon.com.)