All boolean terms are available, but watch out for NOT. You can't use it by itself in AltaVista. In order to exclude terms you must type AND NOT.
Use NEAR to find documents containing your search terms within 10 characters of one another. (That's what they said, but it seems like it's really within 10 words of one another.)
Use quotation marks around phrases
You may use plus (+) and minus (-) signs in place of AND or NOT.
You can enter keywords in the RANK section. This will bring to the top of the list pages containing words typed there.