I just found the favorite tag (it has currently 21 questions). I think it needs to get removed, because...
- ...it doesn't make any sense to tag a question with it
- ...if it makes sense, it should belong on the meta site
- ...there is not a clear usage for it. Question tagged with it are related to the Twitter-, Facebook-, YouTube- and Android APIs or are talking about a custom favorite button and even about a SQL query (and the worst question is talking about 'favourite icons' instead of favicons...)