Foxit PDF Editor.
The conventional Adobe Acrobat Reader has always been a pain, bulky in size (latest version 7.0.8 is about 17MB), takes like forever to open the .PDF files if you have more than 10 windows open at a time, most of all cannot edit the .PDF files in it. Foxit is considerably smaller in size just about 1.4 MB in size, opens .PDF files at a faster rate (about 20 times faster) and has features of a real editor.
Once I made the switch to FoxIt, I never looked back again.
Foxit is free to try, full version can be downloaded here
All the features can be used in the evaluation version just when a modified PDF document is saved, an evaluation mark will be put on every page you modify with Foxit PDF Editor. They also have Foxit Reader(just for reading .PDF files no editing can be done), free for non-comercial use.
Check out there products here