I wrote a long post on the launch of AskEraser at Search Engine Land, titled, Ask.com Launches AskEraser Giving Searches Ability To Search Anonymously. But honestly, if you think about it, AskEraser does not erase data, it is a bad name.
AskEraser just prevents data from being written to Ask.com's servers. It is not like data is being written and then Ask is erasing the data. It is simply not being written in the first place. So maybe Ask.com should rename the tool to something else?
Anyway, if you go to Ask.com, you should see a link to AskEraser. When activated, it won't store data such as IP address, User ID, Session ID, and the complete query text in their databases, cookies or log files for that search. If you turn it off, it will store that data. If you turn it on, you won't get Ask personalized results.
Here is what it looks like:
Forum discussion at WebmasterWorld.