I usually format my laptop every 4-5 months. Next time I format, I'll need less time to get it working again. The reason is that I will install less than half of software I have now.
I already use online applications to do most tasks that I needed software in the past and by next format I will do even more online.
First of all, it's MS Office. I'm using Google Docs and Spreadsheets more often and I'm confident I don't need Office anymore.
Part of MS Office is Outlook. I've almost replaced it with Gmail. It allows me to read my emails on mobile with one click and search is much faster than Outlook's. I use email less anyway as a lot of my communication has been transferred to Zuni and Facebook.
Then it's Visual Studio and MS SQL Server and related software. Well, I don't program on .NET environment anymore, so I don't need them. Now, I only write PHP code and use MySQL.
I also have Wamp Server installed so that I can test code I write for Zuni when I'm offline. But I haven't used it for months as I'm never offline.
Next software I don't need anymore is EMS, a MySQL manager. After some changes we are making at our databases, they work fine at phpMyAdmin, so I will not miss EMS.
Two programming tools that I haven't found an online replacement for are Windows Grep that allows me to replace code in multiple files and WinMerge that allows me to compare two files.
Another application I think I still need to install is Skype. For all other IMs I can use Meebo.
And I also need CDBurnerXP, Paint.NET and SUPER. I'm not sure if I can live without Filezilla, but I can try. And I forgot to mention Firefox.
Finally, I need iTunes that automatically keeps my iPod always updated with fresh podcasts.
Did I mention that next format will be the last one that I'll install Windows?