It's Sandra Bullock's party, and she can dance if she wants to!
"She arrived early in the evening and spent some time with her guests sitting at the bar."
Then Sandy and her pals hung out at a private table, getting giggly with some complimentary champagne.
But it wasn't long before Sandy felt canned Heat in her heels and just had to get down! The source says:
"She emerged with her guests and they danced on the dance floor with partygoers until late in the night.
At one point, she went and pulled her hair up in a ponytail because it got hot on the dance floor. She was laughing and having fun and seemed very relaxed."
No word on whether Lil Jon played.
Ch-ch-check out the pics (below) to see Sandy showing off all her best moves on the red carpet too!