Giovanni Ribisi -- I Dropped $3 Million To Live Next Door to Brad Pitt & Angelina Jolie

Giovanni Ribisi KNOWS one house in L.A. just ain't enough -- the actor dropped $3 million on a sweet new pad in the Hollywood Hills ... just 5 miles down the road from his OTHER sweet, new pad.

Ribisi's recent purchase is 3,756 square-feet of awesomeness -- it boasts 5 bedrooms, 5 baths, a library, lagoon style pool, cascading waterfall ... AND sits right next door to Brad Pitt and Angelina Jolie (awesome?).

All in all, the crib set Ribisi back a cool $2.95 million.

It's house numero dos for the "Ted" actor ... 3 months ago he dropped $1.4 million on a sick new 2-bedroom, 2.5-bath house in Atwater Village complete with an artist's studio -- only a few miles away.