I use TOOfaced lip injection
http://www.toofaced.com/product.asp?cat_id=65&dept_id=1
I haven't really noticed until now that it says it's supposed to achieve a long term effect. haha I don't use it very often. I've tried the Sally Hensen but that one is nothing compared to this one---Toofaced REALLY STINGS. haha but I don't think it makes a HUGE difference though.. Angelina lips? no. at least not for me.

oo anyway I found this that describes it:
The way this product works is the cinnamon oil contained in the ingredients is a common irritant to the skin. This irritation is amplified when placed on one of the thinnest skinned, and most sensitive areas of your body -- your lips. The burning, stinging sensation you feel is your lip letting you know there is an irritant on your lips. Your body's natural response to this irritant is to send extra blood to the area of irritation to try to protect it from harm. The extra blood flow in the lip area, due to the irritation, is what makes your lips appear 'fuller.' Most lip plumpers on the market today work to 'plump' your lips through this process of irritation.

The more cinnamon oil a lip plumper contains, the more irritated your lips will become and the fuller they will look. Because of the irritation and subsequent blood flow increase, your lips will also look darker.

While they do work to make your lips look slightly fuller, don't expect a miracle here, lip plumpers containing cinnamon oil are not for everyone. If you have 'sensitive skin' you will most certainly hate this product. DO NOT put this product on a dry or sensitive lip or the sensation will move from irritation to pure pain. God forbid you get this stuff in a cold sore, split lip, sun burnt lip or any other open mouth wound or you will want to slice your lips off. You may not realize you have tiny, dry cracks in your lips until this stuff gets in there. Ouch! I find this especially irritating in the corners of the mouth.

If your new lip look generates some amorous advances and you find yourself kissed, you will transfer all this wonderful stuff, and all the irritating side effects, to your kissing partner. Whoops! Your gig is up! The illusion of sexy sensuality will all be shot as your kisser declares, "What's that!? Why are my lips on fire!?" Angelina Jolie you are not.

The results are moderate and for some, the sensation is tolerable. It's up to you to decide if it's worth it.
taken from: http://www.amazon.com/Too-Faced-Lip-.../dp/B0002QNMUM