Fred Kittler, co-founder of Velocity Technology and Communications Fund, a hedge fund focusing on the high-tech sector that in 1999 was up 262 percent, after fees, is testing F. Scott Fitzgerald’s assertion that there are no second acts in American lives. Kittler, who, like Fitzgerald, attended Princeton University as an undergraduate, believes a relatively new investment sector called cleantech is about to take off, and with it the returns of his new hedge fund firm, five-year-old Palo Alto–California based Firelake Capital Management.