We have a source-error tag, which was the pet project of one particular high reputation user who hasn't been around for more than a year and a half. It seems that since they left, no one else has thought it was a good idea to tag "typo" questions in this manner. (This tag was previously known as typo.)
This has been previously discussed in meta comments, where the chief proponent of the tag wrote:
Voting to closing is fine. I also tried that in the past. But five votes are required, and as I wrote in the description of the tag, it usually does not get closed. The tag was a workaround for the problem.
I don't think this is a valid solution to the perceived problem. If the questions should be closed, we should close them; we shouldn't tag them "please ignore this question, it should be closed". I think that the source-error tag is a meta tag; it could never appear on its own because it doesn't tell you anything useful about the question content itself.
I've brought this up on chat before, and so has Troyen, but it looks like we've never gotten around to removing the tag. Shall we?