UPDATE: The most current version of this list can be found at: The Home of the Social Networking Services Meta List.
I have marked all new updates to this list, since 01 May 2004, with an asterisk (*).
Comments, links, and recommendations for additions and deletions are welcome-as always.

business networking sites
Affinity Engines, Business Parc, The Conneck, Contact Network, Corporate Alumni, ecademy, eConozco, Eliyon, EntreMate, Friendly Favors, GoingProfessional, Growth Company, I'm Not From Here, InterAction, ITmob, ItsNotWhatYouKnow, Join Network PLUS, LLC, Konnects, LinkedIn, Link Silicon Valley, matcheroo, Mediabistro, Monster Networking, NetMiner, Netmodular Community, Networking For Professionals, Online Business Networking Resource, Open Business Club (openBC), OrderGenerator, Point Relevance, Polypol, PowerMingle, RealContacts, ReferNet, Reunion, Ryze, SelectMinds, Shortcut, Silicon Valley Pipeline, Spoke Software, Sullivan Executive Networking Community, Tacit - ActiveNet, TENG, Visible Path, WisdomBuilder, Zerendipity Networks.
common interest networking sites
50 Something.com*, 50Yearsplus.com*, ANTfriender, ArtistNow!, AveMariaSingles*, Bigcampus.net, BookCrossing, Buzznet, Classmates.com, Collegester, Community Zero, Company of Friends, DeanSpace, Delphi Forums, Digital Squeeze, Downelink, Foodsters, FunHi, GamersGlue, Globe Alive, gradFinder, HRTS - Hollywood Radio & Television Society, Mediabuddies*, Meet Me at HOT or NOT?, Netplaya Burning Man Community, Neurona, PayDemocracy, quad5*, Schoolster, SongBuddy, Talk City, Thefacebook, TheSquare, threedegrees, UpMyStreet.
dating sites
AfroRomance, americansingles.com, Amigos.com, AsiaFriendFinder, Berkzter, BlackPlanet.com, Cherish, collegeluv.com, Country Singles, Cupid.com, Date.com, Dating.dk*, eHarmony, Equally Yoked, FriendFinder, Gay Christian Dating*, Gay Jewish Dating*, Gay Military M4M*, GermanFriendFinder, hotsaints, IndianFriendFinder, jdate.com, Lavalife, LDS Singles Mingle*, LDS Singles Network, LDS Singles SingleSaints*, Love.com, M4M Seniors*, Match.com, Mature Dating.org*, meetic*, MyCountryMatch*, MyEMatch, Overweight Date, Passion.com, POP! PeopleOnPage, PlanetOut Partners, Inc., RateOrDate, RedDate.com, Relationship Exchange, Senior Dating Exchange*, SeniorFriendFinder, SeniorsCircle.com*, Single Seniors*, Spicy Senior Singles*, Swappster, TrueBeginnings, uDate.com, Vegetarian singles, webdate, Yahoo! Personals.
face-to-face meeting facilitation sites
8minuteDating, Evite, First Tuesday, The Lunch Club NYC, MeetUp, MixerMixer, Netparty, new-in-town, Social Circles, WhizSpark.
friend networking sites
Backwash, Breedster, BuddyBridge, Chia Friend, ChosenNet*,Christianster, Click2Friends, easeek, eFriendsnet, enCentra, everyonesconnected, FriendFan.com, Friendity, Friend MAP, Friendoo, friendsbay.de, Friends of Friends, Friends Reunited, Friendset, Friendster, Friend Surfer, Friendzy, Gruuve, HeiYou, hi5, hipstir, Huminity, HummingBoard, The Impersonals, iSocialite*, Korea Data House, LDS LinkUp*, LianQu, linkyourfriends, Living Directory, Metails, mrNeighborhood, Myspace.com, NetFriendships, Neurofriends, orkut, PalJunction, peeps nation, qpengyou, Ringo, saywhatz, Tickle by Emode, ticqle, Tribe.net, UUFriends, Wallop, WiW, WorldShine, YeeYoo, YOYO, zenetwork, Zerodegrees.
pet networking sites
Backwash for Pets, Dogster, HAMSTERster, KissyKat, Neopets.
social networking 'plus' and/or 'edge cases'
Blogpod, BuddyZoo, del.icio.us, dodgeball, Dude Check This Out!, eTwine.com*, Eurekster!, eventSherpa, Expressions, Findapix, Flickr, fonetango, Fotolog.net, Funchain.com, Gush, HelloWorld, Home Exchange, HomeLink, Intervac, JournURL, KnowMates, LiveJournal, MixedNutz.net, Mooble, M-Tone, Multiply, Nioki, The Opinion Exchange, Palbook, PeopleAggregator, Plink, RepCheck, SmallPlanet, Small World Project, SocialCanvas, Social Grid, Squiby, StumbleUpon, TXTParty, Upcoming.org, WiredReach, Yafro Moblog, Zdarmanet, Zopto.









1. I think that instead of a monolithic list, it might be more helpful to provide some type of ranking system here.
Posted at 8:04PM on Dec 18th 2005 by Gina Bianchini