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Im not even going to read this thread because I already know how to answer and no one is gonna like it.

Get an SSD.

I have one, Lion is fast... actually booting, rebooting, shutting down, saving apps, resuming apps is all instant.

Join us in 2011 and leave your mechanical HDDs behind and get with today.

Yeah, I know. Blah Blah you dont have enough money or need the space a HDD provides. We have heard it all before. We have no sympathy for you - just go get an SSD or use Snow Leopard until your mechanical hard drive dies.
 
Fonts

If you have a lot of fonts, check them using Fontbook app.

In my case Lion activated more than 5000 fonos I had in stock and that alone made the Mac completely irresponsive affecting several applications.
 
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