AllSearchEngines.com (listing of "all" including a listing of top search engines by "type")
AltaVista (one of the oldest crawlers)
Ask.com ( human powered engine)
CNET's Search.COM (metasearches over 800 specialized search engines)
Direct Search (contains links to over 800 resource specific search interfaces better designed to uncover information often missed by the big search engines)  
Dogpile (metasearches many of the most popular search engines)
Google (one of the most popular with the largest collection of pages of the crawlers)
Google Unclesam (searches only govt. web pages)
HotBot (owned by Lycos, but run as a separate service)
Infomine (human powered web directory)
Internet Public Library   (human powered web directory)
Invisible-web.Net  (companion to book of same name, provides a directory of mostly free sites not available through other search engines)
Librarians Index to the Internet (human powered web directory)
LookSmart (human powered service)
Lycos  (directory model similar to Yahoo)
Metacrawler  (metasearches many of the "best" search engines)
MSN (web directory powered by Looksmart)
The Wayback Machine  (Internet Archive offers a way to "surf the web as it was")
WebCrawler (human powered engine)
Yahoo (human powered web directory)

AccuNet/AP MultiMedia Archive (CSULB Database--requires authorization for off campus use)
All the Web Click on "pictures" or "videos"
AltaVista Image/Photo Finder
Ditto.com
Google Image Search
Lycos MultiMedia Search
MIDI Explorer
The NYPL Picture Collection Online
PicSearch: the Search Engine for Pictures and Images
U.S. Government Graphics  (most of these graphics are in the public domain and can be used without permission)