Ashton Kutcher and Mila Kunis Celebrate New Startup at SXSW

Since becoming a dad in October, Ashton Kutcher is ready to tackle his next project – a venture capital firm – with fiancée Mila Kunis by his side.

The Two and a Half men actor, 37, and investment partner Guy Oseary, 42, launched Sound Ventures at the South by Southwest festival in Austin, Texas, on Sunday.

Inside Madonna's A-List Oscar Party

Madonna’s annual post-Oscars party was the place to be after Sunday night’s show.

The bash, held at her pal Guy Oseary’s Los Angeles home, went on until 4 a.m. Celebrities were “wall to wall,” a guest tells PEOPLE. “Everyone was dancing, mingling and eating.”

Academy Award winners past and present let loose and dined on dishes such as Caesar salad, penne pasta with red sauce, rice and chicken in a curry sauce and potato knishes, served buffet style.