The terms for the deal were not disclosed.
Zapata shares were up nearly 1 percent at $17.38 in early trading. The stock has traded at a high of $24.94 and a low of $4.63 during the past 52 weeks.
Earlier this week, Zapata announced its intent to acquire or invest in 22 other Internet sites and e-commerce businesses in an effort to expand Zap, its Internet portal. Zapata estimates Zap will be among the largest Internet sites based on the number of users if all 23 deals are consummated.
CoolChat features online chat rooms, personal advertisements, free home pages, threaded conference forums, and message boxes.
In May, Zapata announced that it was splitting itself into two companies, with the newly formed Zap concentrating on Internet ventures. Zapata was to remain a marine protein and food packaging company.
Also in May, Excite, a online search engine rejected a $72-per-share unsolicited bid from Zapata.