Invite-Only Index

There are a number of reasons you could create an invite-only Web service, such as privacy or beta testing, but the number one reason is to create an air of exclusitivity and keep people out. How many of these sites are you in?

I will not invite you to these services. Yes, I am registered on most of them; no, none of them are amazing or life-changing.

Interesting invite-only services

Service	Invite System	Behind the Curtain	Difficulty
~~Gmail~~	You get 10 50 100 invitations at random points.	A great e-mail service.	No longer invite-only
~~Friendster~~	Everyone who you add as your friend gets an invite.	A social networking service.	No longer invite-only
~~Wordpress~~	You get one invitation.	A URL for your blog	No longer invite-only
Orkut	Everyone who you add as your friend gets an invite.	A social networking service.	Open
Yahoo 360	Everyone who you add as your friend gets an invite.	A social networking service.	Open
Mixi (ja)	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
Kinugasa (ja)	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
Gree (ja)	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
Grono (pl)	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
iWiW	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
Wallop	Everyone who you add as your friend gets an invite.	A social networking service.	Exclusive
Gawker	You get random invitations.	You can post comments on Gawker articles.	Exclusive
Humhum	Unknown	A forum, perhaps other services.	Very exclusive
FilePile	Unknown	Filesharing, perhaps other services.	Very exclusive.
aSmallWorld	If you have 50+ connections, everyone who you add as your friend gets an invite.	A super-elite forum for celebrities and jet setters, used for trading secrets of the rich.	Very exclusive

Uninteresting invite-only services

Service	Behind the Curtain
30gigs.com	A worthless e-mail service with less than 1GB of storage.
Web2Messenger	Some dumb MSN thing.
Xasamail	E-mail and Jabber
Greek Union	A social networking service.

Invite-only social networking services are so popular in Japan that they have several open source engines (OpenPNE, Affelio, etc.) There are 50-100 minor ones that I haven't listed here.

Invite-Only BitTorrent Trackers

BitTorrent sites are not meant to be exclusive; they are often invite-only for security and server load reasons.

Invite-Only Tech Conferences

LiveJournal and IRC

Everyone on LiveJournal has the chance to make their entries available to a small group of friends. This isn't like invite services because only the person posting entries can invite others, and it's based around a sense of privacy rather than exclusitivity; but it is extremely popular among LiveJournal users and probably the combined number of people begging to be added as LJ friends exceeds the number asking for service invites on a daily basis. So, if you're writing about invite-only things make sure to mention LJ.

IRC channels can also be invite-only, but because IRC is so temporal only a few channels (like #twilight_zone) are asinine enough to do this.

Suggestions

Please post comments and suggestions to my BBS.