a must have widget is istat pro. it tells you all the stats about everything like how much ram you have free, cpu usage, HD space, system temperature, and fan speed. there is also something called istat menus that does the same thing but it displays the system stats on the menu. heres a pic: you can download it >HERE<
Ha I just downloaded that the other day, it is pretty cool. I don't have it in my status bar though, I kept it in my Dashboard.
I can't live without Notational Velocity to take quick text notes. Evernote can do so much more but I really just need text notes and NV is so fast and sleek. I used the option to save the notes into individual text files and sync its folder in Dropbox, this way I can also access to my notes from the iPhone when I'm around.
