Dictionaries/Directories & General Reference
Merriam-Webster Dictionary/Thesauri
Refdesk.com - Encyclopedias, dictionaries, atlases...
U.S. Postal Service - Zip Codes
University at Buffalo Libraries-References on the Net - A good source for general references available on the Internet.
The WorldWideWeb Acronym and Abbreviation Server
Google Maps - Driving directions and maps