avoiding tag misspellings an erroneous tag data

I'm开发者_JAVA技巧 working on implementing a tagging system in my application. I've been reading some of the other questions on SO about database schemas used to implement tags and they've been very helpful, but I havent' found any that talk about how to combat tag spelling errors and things. So if two people enter the same tag but they are spelled incorrectly, it becomes a problem when others go searching for tags, or if you want to do any reporting off of tag information. What kinds of things to others use to help avoid this? or do you just have to put up with it?

Having moderator-level community members can assist in this event. The re-tagging of things should be able to be flagged by a member, changed by a moderator. The same goes for question alteration, title changing (for clarity). Community driven databases are good for this, given effective scoring system to prevent malicious editors.