like in Yahoo and most places i type in a search field, it shows up past searches in a drop down bar. how do i make it not do this

lol why oh why would you not want it to display what you have been searching for 5liter?

well, 1) its annoying
2) ...the obvious...
3) it serves no advantage to me anyways

That feature is called AutoComplete and I have no idea how to turn it off.
You can scroll down and hit the delete key and remove the past searches. That's what I do.

You porn fiend, you.

Tools --> internet options --> Advanced tab. Scroll down just a little and there's one called Autocomplete uncheck that box.