SharePoint and Querystrings

Recently did a little bit of playing with querystrings (at the end of the URL, that is after the .aspx, put a '?' then the value below, to use more than one use an '&'), thought it might be something other people are interested in. Strange that I haven't really stumbled across these documented anywhere else, it might just be that I haven't been reading the right documents! (I'm sure that if this is the case it will be politely pointed out to me!)

Let me know if you have any others and I will add them to the list.

Finally (there is always a finally isn't there?) a couple of things that should be considered:
1. These querystrings *will* respect the underlying SharePoint permissions, so for example, someone without the ability to add web parts will not suddenly be able to by using these querystrings.
2. These will let you add web part to pages that may not have been designed to have web parts added to them, for example the "Sites" page. Be very careful as there are certainly some issues to be discovered, don't try and get too fancy!
3. You use these at your own risk.