1. Zynga — $180 million for social games on Facebook. Investors: Digital Sky Technologies, Institutional Venture Partners, Andreessen Horovitz, Tiger Global.

2. Playdom – $43 million for social games on Facebook, MySpace and other platforms. Investors: Rick Thompson, Lightspeed Venture Partners and Norwest Venture Partners.

3. Smith & Tinker — $29 million (includes seed round) for hybrid web-toy Nanovor game. Investors: Alsop Louie Partners, DCM, Foundry Group, Leo Capital Holdings and billionaire Paul Allen’s Vulcan Capital.

4. PopCap Games — $22.5 million for casual games (such as Plants vs. Zombies, pictured) on the web, mobile, and social networks. Investors: Meritech Capital Partners, Larry Bowman and John McCaw.

5. Zula — $20 million for science-based kids virtual world, Zula World. Investors: anonymous investor.

6. Zynga — $15.2 million for social games on Facebook. Investors: Kleiner Perkins, Foundry Group, Avalon Ventures, Institutional Venture Partners and Union Square Ventures.

7. Offerpal Media — $15 million for special offers for online social games. Investors: D.E. Shaw, Interwest Partners and North Bridge Venture Partners.

8. Emergent Game Technologies — $12.5 million for game development tools. Investors: Hopewell Ventures, Worldview Technology Partners, Jerusalem Venture Partners, Walker Ventures and Adena Ventures.

9. gWallet — $12.5 million for virtual currency and offer provider. Investors: Adams Street Partners, Trinity Ventures, Stanford University and others.

10. SendMe – $12 million for direct-to-mobile entertainment and games. Investors: Triangle Peak Partners, Spark Capital, Amicus Capital, GrandBanks Capital, and True Ventures.

11. Caustic Graphics — $11 million (announced in 2009, raised earlier) for ray-tracing graphics chips: Investors: undisclosed.

12. IMVU — $10 million for 3-D virtual chat rooms and virtual goods business. Investors: Best Buy Capital, and existing investors Menlo Ventures, Allegis Capital, and Bridgescale Partners.

13. Ngmoco — $10 million for iPhone games (pictured) and Plus+ social gaming platform. Investors: Norwest Venture Partners, Kleiner Perkins.

14. Nurien Software — $10 million for realistic fashion-oriented virtual world. Investors: Northern Light Venture Capital, Globespan Capital Partners, New Enterprise Associates, and QiMing Venture Partners.

15. Super Secret — $10 million for kids virtual world. Investors: Opus Capital.

16. Scene Systems — $8.3 million to use video game tools to reconstruct accident scenes. Investors: Philip Swinstead, Cem Cesmig (Newtonmore Advisors), Sophia Antipolis, and Caprilles Investment Fund.

17. Asetek – $8 million for liquid cooling for game PCs. Investors: Northzone Ventures, Sunstone Capital, and KT Venture Group.

18. Bigfoot Networks — $8 million for faster networking cards for gamer PCs. Investors: North Bridge Venture Partners, Palomar Ventures and Raven Venture Partners.

19. Outspark — $8 million for free-to-play massively multiplayer online games. Investors: Syncom Venture Partners, SBI Investment, Mille Plateaux, DCM, Tencent and Altos Ventures.

20. Riot Games – $8 million for real-time fantasy combat game, League of Legends (pictured), on the web. Investors: Tencent, Benchmark Capital, and FirstMark Capital.

21. Greystripe – $7.5 million for mobile ad network for games and other apps. Investors: Peacock Equity, Incubic Venture Fund, Monitor Ventures and Steamboat Ventures.

22. Major League Gaming — $7.5 million for professional gamers league. Investor: Oak Investment Partners.

23. Dreambox Learning — $7.1 million for educational games site. Investors: variety of tech industry angels.

24. Six Degrees — $7 million for sports-related web games at Action All Stars site. Investors: Time Warner Investments. Clearstone Venture Partners and Prism VentureWorks.

25. WonderHill – $7 million for online casual games such as Green Spot and Dog World. Investors: Charles River Ventures and Shasta Ventures.

26. Ohai — $6 million for massively multiplayer games on Facebook. Investors: August Capital and Rustic Canyon Ventures.

27. Posit Science — $5.6 million for brain-training games. Investors: Aberdare Ventures, Cooley Godward Kronish, Draper Fisher Jurvetson and VSP Capital.

28. Conduit Labs – $5.5 million for Loudcrowd social music game site. Investors: Charles River Ventures and Prism VentureWorks.

29. Unity Technologies – $5.5 million for browser-based 3-D game engine. Investor: Sequoia Capital.

30. Watercooler — $5.5 million for sports-based social networking games. Investors: Betfair and Canaan Partners.