Elevation seeks $1 billion with help from U2's Bono

U2 frontman Bono is embarking on a solo tour but it doesn't involve music. A private equity firm co-founded by the musician is hitting the road to search for more money, according to Reuters.

Elevation Partners, which has invested heavily in social networking, is now looking to dig up $1 billion for a second fund, reports Reuters. The company's largest investment to date has been in Facebook, to the tune of $270 million, which came in three installments and valued the social networking site at $16 billion at the time. (The company is now estimated to be worth $100 billion.)

The share that Elevation owns in Facebook is 1.5 percent, which should give the firm a hearty return since the social network filed for a $5 billion initial public offering last month.

Besides Facebook, Elevation has also invested in Yelp. After an initial investment of $25 million in 2010 that valued the company at $500 million, Elevation then committed to invest up to $100 million in the coming years. There should be a good return on this investment too since Yelp went public this month and so far its shares seem to be doing strongly.

Other less lucrative investments Elevation has made were in smartphone maker Palm and "Forbes" magazine.