If you have a different bachelor's degree already, Oregon State has an online post-baccalaureate degree program.
I'm in that program and it's pretty challenging. They don't skimp on the workload because its online, and the degree is the same as their in class degree.
When I was researching this back in the day, this was the only program I found through a regular state university for online computer science. There may be more now, though. I know that a few schools like ASU (Arizona State) are adding engineering programs that are either competely online or mostly online with the exception of lab portions. More schools may add computer science to that as well.