Google won't let me search now.... I am a computer virus

Today, I was trying to search for twitter desktop clients and I entered the query "twitter desktop clients" in the search bar in IE 7. It was a nasty early morning surprise to see that I am forbidden (HTTP 403). Check out the image below.

(click to see larger image)

Has anyone else seen this … ?

Google, what is going on?

Update: Does anyone know how to fix this problem? They ask me to verify a visual cue but don't seem to have a submit button to go along with it.