The short messages (140 chars.) sent on Twitter, often via cellphones, are ideal for spreading the word rapidly. Twitter contests can work for local business. Moonfruit, a website design company, gave away 10 MacBooks in 10 days to attract 10,000 new followers per day from this promotion.
Follow your local community Twitterers via Localtweeps.com, Chirpcity.com and Breaking News city sites, or Twitter directories with local city tagging like Twellow.com or WeFollow.com. Then create a contest campaign that will generate a buzz.