Recently I've been wondering if anywhere does good ones online that I could do in my spare time or whether it's even a good idea?
Specifically being a UK resident I'd mainly like one to more easily attain a H-1B visa but also to perhaps go over some of the deeper concepts again.
Note: I've been doing 'nix/python/perl for about 7 years professionally and also don't have a degree. I've actually been using the Khan Academy to re-learn some of the more advanced Algebra and Calculus bits I forgot a little bit each night for the past few weeks. When I'm done, I'll likely find a college that will do night school CS. Not because I need it, but because I want to have a degree. Having used Linux as my primary operating system fulltime for the past 12 years, I can honestly say I could teach just about any of the Linux/Unix classes. But it is good to have accomplished something.
[1] http://www.cs.princeton.edu/~rs/ and http://www.amazon.com/Robert-Sedgewick/e/B000AQ4JCO
If so bite the bullet and go full time to a decent university. Many will take your professional experience in lieu of academic credentials.
Contact the admissions departments at your chosen institution to find out if you qualify before applying through UCAS.
Any STEM degree can lead to a H1-B visa provided you can find an employer.
Edit: That's California State University, Northridge (Los Angeles County, CA - USA).
Here's their Computer Science department website: http://www.csun.edu/engineering-computer-science/computer-sc...