Essential software for improving one's game?

I'm sure this has been covered many times before, sorry for the rehashing. I appreciate the collective wisdom here and any opinions will be appreciated.

What software applications have you found most helpful for your play and why? I play alot of 100+9 1 table SNG, and 33 multi table and 100 multi. I play for fun and the challenge, making money is a cool bonus. Pretty much just jumped up to these limits and have more than held my own. I study. I think. I try and get better. I have a ways to go. So, I know that there are a number of tools out there that would really benefit my game. What software does a serious player need? Why do you recommend that software? I've just ordered a new laptop and want to get it slicked out with poker gear.

Thanks in advance for your thoughts.


Zenpractice

You'll find that most everyone here would reccommend poker tracker from www.pokertracker.com to use in combination with poker ace http://www.pokeracesoftware.com/.

The third essential piece of software would be Sit-N-Go Analyzer from http://www.sitngo-analyzer.com/ other people have reccommended Poker Spy www.poker-spy.com