What about the Lido, an 11-mile-long sandbar that's home to about 20,000 residents? It's a 15-minute ferry ride from Venice proper, plus you can catch ferries to the airport and places like Murano. My wife and I stayed here while visiting Venice in November several years ago; accommodations are cheaper here than on Venice, plus you get a nice view of all the historic buildings and churches as you ride the "Vaporetto" (aka, water bus) each morning. The Lido is also the venue for the Venice Film Festival each September, plus has a touristy beach area that's popular in summer.