Ask HN: Twitter style StackOverflow?

Every time I ask something on StackOverflow, or on any other forum for that matter, I keep on refreshing the page to see if anyone posted any replies. Just now it came to my mind - could this be done via Twitter (hashtags, to be specific)?

To ask a question, just add a hash tag to your question (lets say #someonepleaseanswerthisasap, or something better) and tweet it. People can just track this hashtag, and answer whatever they feel like answering.

Might sound like like Aardvark, but on top of Twitter. Does this sound weird, or possible?