I use a widget to take my screenshots. It has a great interface, easy to use, yet powerful preferences. It’s easy as:
1. Choose what you want to shoot
Widgets
Selection
Full Screen
Window
2. Shoot
It shows up right on your desktop, and you can open it in preview, and take amazing transparent screenshots. Check it out and download it at [...]

There is a very easy way to drag multiple widgets off the dashboard permanently. Go into terminal; type:
defaults write com.apple.dashboard devmode YES
Log out, and log back in. Open dashboard, drag a widget either from the widget bar, or the dashboard, press F12, and let go. Give it a couple seconds, and when you go back [...]