You're not going to find a lot open in the immediate LAX area. People used to rave about the 24 hour cafe at the Hacienda Hotel, but the hotel closed. It's now Aloft and a Fairfield Inn. You can check to see if there's still a 24 hour cafe there. There's also an IHOP north of LAX at Sepulveda and Manchester that's open 24 hours. Near The Grove there's Du-Par's at the Farmer's Market, which is open 24 hours. I'd read reviews, because while it's very nostalgic for me, that service wasn't great the last 2 times I was at that location. Also in the general area, Joan's on Third, Doughboy's or Toast Cafe. If you want to go for a destination, look at The Griddle Cafe in West Hollywood. For something near the Science Center, I'd look downtown. The Pantry is open 24 hours, there's also Grand Central Market.