[eluser]Ki[/eluser]
Have a look at sphinx search. This is the workhorse of full text search and fantastic results (about 100 times faster) then MySQL. I have a very active site with about very large database and all my queries are handled through sphinx with a search time of about 0.05 sec.
Keep in mind, that if you are using MyISAM because you need full text search, your table gets locked every time there is a write. Offload search capability, and you can move to innodb, which has a row level locking and your queries will run significantly faster.
Its a bit consuming to implement, but long term results are well worth it.