James Green-Armytage has a great page on his website about a system of Direct Democracy via proxy voting that I think should be included here.
BeyondPolitics.org is dedicated to delegable proxy, and suggests that delegable proxy used as a communication tool in what are called Free Associations may be an integrative and inclusive social change mechanism that bypasses existing systems. Beyond Politics and Beyond Politics Wiki
Further, delegable proxy, combined with an initial secret ballot, has been suggested as an election method (which might incorporate other elections methods) for use in situations where security or other concerns require voter anonymity. See Delegable Proxy Election, DPE.