THANKS Thanks go to many people who have helped in the developement of xpg during this year. I would like to thank all members of the HUJI CS system group, who were all bothered by my many questions but still answered most of them... Thank you Izar, Ilya, Misha, Michael, Danny, Amos, Gali, Guy and Ariel. Thanks go also to the office of CS which tests and uses xpg. Special thanks go to Jorge Najenson, who has helped me alot in designing xpg, who has come up with the original idea, and who has coordinated everything between the author and the office of CS. Special thanks go also to Prof. Yehoshua Sagiv, who has gave the academic support needed to make this project a serious one. Last special thanks go to Aviv Shavit, who has worked with me on too many projects this year, and who had to suffer from my hard work on this project... And thank you all future donators who will make this project even sweeter ;)