1. Species Morphing
1.1. Dragons
1.2. Furries
1.3. Nekos
1.4. Tinies
2. Academic
2.1. Librarians
2.2. Sociologists
2.3. Educationalists
3. Arts
3.1. Art
3.1.1. Photography
3.1.2. Sculpture
3.1.3. Digital Art
3.2. Machinima
3.3. Music
3.3.1. DJ
3.3.2. Performance
3.3.3. Internet Radio
3.4. Theater
3.5. Broadcast Drama
3.6. Live TV
3.6.1. Business
3.6.2. Entertainment
3.7. Newspapers/Magazines
3.8. Drawing & Painting
4. Corporate
4.1. Research VW's
4.2. Global Collaboration
4.3. Marketing
5. Professional
5.1. Architectural
5.2. Medical
5.3. Scientific
6. Sexual Preference
6.1. BDSM
6.2. GLBT
6.3. Misc. Fetish
7. Technology Extenders
7.1. Client coders
7.1.1. RLV
7.2. OpenSimulator
7.3. Bot Builders
8. Alternative Communication
8.1. GTalk
8.2. AIM
8.3. Skype
8.4. iPhone Apps
8.4.1. TouchLife
8.4.2. Sparkle
9. Support Groups
9.1. AA in SL
10. Non-Profit
10.1. Volunteerism
10.2. Outreach
10.3. Advocacy
10.4. Fund-raising
10.5. Philanthropic
10.5.1. NCI
11. Government
11.1. Federal
11.1.1. Military
11.1.1.1. Recruitment
11.1.1.2. Training
11.1.1.3. Family Outreach/Support
11.1.2. Civilian
11.1.2.1. DOE
11.1.2.2. NASA
11.2. State
11.3. Local
12. Science
13. Personal Publishing
13.1. Blogging
13.2. Podcasting
14. Media Sharing
14.1. Flickr
14.2. Koinup
14.3. YouTube
14.4. VodPod
14.5. Vimeo
15. Social Networking
15.1. Facebook
15.2. Plurk
15.3. Twitter
15.4. Ning
15.5. LinkedIn
16. Web Platforms
16.1. Shopping Sites
16.1.1. Individual
16.1.1.1. Hippo
16.1.2. Open
16.1.2.1. Apez
16.1.2.2. Xstreet
16.1.2.3. Slapt
16.1.2.4. Metalife
16.2. Social Sites
16.2.1. Designer Showcase Network
16.2.2. MetaMoo
16.2.3. AVMatch
16.2.4. Forums
16.2.4.1. SL Universe
16.2.4.2. SLInside
16.2.5. Wikis
16.2.5.1. SL Wikia
17. Meetaverse
18. Literary
18.1. Library Systems
19. Building/Scripting
20. Griefing
20.1. Trolling
21. Nationality
22. Religious
22.1. Buddhist
22.1.1. Multidenominational
22.1.2. Traditionalist
23. SL Business
23.1. Retail
23.1.1. Fashion
23.1.1.1. Skins
23.1.1.2. Hair
23.1.1.3. Clothing
23.1.1.4. Shoes
23.1.2. Avatars
23.1.3. Vehicles
23.1.4. Weapons
23.1.5. Home & Garden
23.1.5.1. Furniture
23.1.5.2. Buildings
23.1.5.3. Plants
23.1.5.4. Animals
23.2. Services
23.2.1. Scripting
23.2.2. Marketing
23.2.2.1. Translations :-)
23.2.3. Design
23.2.4. Escorts
23.2.5. Real Estate
23.2.5.1. Mainland
23.2.5.2. Estate
23.2.5.3. Apartments
24. Gamers
24.1. Fantasy
24.1.1. Based on Fictional Work
24.1.2. High Fantasy
24.1.3. Steampunk
24.1.4. Urban
24.2. Role Playing
24.2.1. Gaming
24.2.2. Historical
24.2.3. Sexual
24.2.4. Family
24.3. SL Sports
24.3.1. Flying
24.3.2. Sailing
24.3.3. Surfing