Mashable has fun list of ways to use Twitter to find a job. Some of the hints:
Tweet Like an Industry Expert
Whether or not you're searching for a job, make sure your Twitter stream represents you as a professional individual that has important and unique thoughts to contribute. Your goal should be to become an industry expert - or at least tweet like one.
Use Hashtags
You can find general job advice and lots of listings through hashtags like #jobs, #recruiting, #jobadvice, #jobposting, or, to get more specific, #techjobs.
Connect with Recruiters and Current Employees
Don't be afraid to research the companies that you want to work for to find out who currently works there and who is involved with recruiting. After all, while you're searching for a job, recruiters are scouring the web at the same time looking for pertinent information about job candidates.
Build a Relevant Network
Twitter is all about networking, so build a network that makes sense for you. You¿ll find that a lot of the opportunities that are presented to you are simply organic.-- Don Willmott