If you are the only person who uses a Windows 7 computer, one thing you can do is have your login information saved so you are automatically logged in when your machine boots up. To accomplish this, I am partial to the the Sysinternals Autologon tool (because it support any version XP and later), however you can configure this directly in Windows 7 as well.

While you can do this on any machine, due to the obvious security implications here, I would only suggest you do this on desktop machines where you trust everyone who has access to the machine. Yes, physical hardware access does trump any software security you have any place, but still you should be careful with using this.