NY Times has taken a look at the funding that the open source projects have received in an article titled "Open Wallets for Open-Source Software"

• February 2004, JBoss received a combined $10 million from two prominent venture capital firms
• Jboss, was one of 20 such businesses that raised $149 million in venture money in 2004, according to estimates by the research firm VentureOne. At least three open-source start-ups raised $20 million last month alone.
• In 1999 and 2000, according to VentureOne, venture capitalists invested $714 million in 71 open-source companies. Most of those projects collapsed.
• A big difference between then and now is the increased adoption of open-source software by corporate users. Another is the relative success of Red Hat, an open-source start-up that went public in 1999 and makes money by selling enhancements and maintenance services to corporations using Linux.
• Red Hat has become something of an inspiration to open-source businesses and their investors because it shows that it is possible to base a lucrative services business on giveaway software. Red Hat also gives its customers a guarantee that a long list of popular applications will work on its edition of Linux. The company had $125 million in revenue in 2004 and now has a market capitalization around $2 billion.
• $714 million invested in open source in 1999-2000