You may use the below already, but there's bound to be someone who doesn't...
Caroline: Ctrl R will make an email that you have already opened appear as unread
Mel S: View - sort by Date, From or Subject - helps you find what you're looking for
Mark (by proxy!): b key gives you a black screen (like using No Show) on the remote control pad
Caroline: and w gives you a white screen
The software Mel G. uses is Windows Media Encoder - free download from internet. Have a go!
Mel S: http://news.bbc.co.uk/1/hi/technology/4849402.stm gives info on latest in technology
Caroline/Karen: http://mm.dfilm.com/live/home.html animated moviemaker online - you need to set up an account and then you can make your own animated cartoons. Easy and results are quite crude but could be fun with students...
For more tips go to the eLL wiki to see the eLL emails from last year with heaps of tips. You can add your own tips there as well.