I haven’t found such an useful widget ever in my life. I have been using Internet for years but never ever stumbled onto something like this. Yahoo Informer is a widget which will keep you updated with stuffs like system resources (CPU usage, disk usage, memory usage, swap usage, system uptime, WiFi, battery life, Recycle Bin/Trash), Internet resources (RSS feeds, IMAP4/POP3 MailBoxes and Gmail Inbox), etc., and all this is displayed right on your desktop!
Note: Yahoo Informer consumes upto 40 MB of space and this depends on the features you keep adding. Although 40 MB isn’t that big when it comes to the kind of works this widget will perform for you but still I thought that I must make a note of this as there are people who like to save their memory like it cost them some millions of bucks.