I moved to the UK (from Ireland). It was relatively painless. No visas, no registration as a foreign worker, just show up and tell the JobCenter you need a National Insurance Number (which took almost a month from the first phone call to getting a cancallation, to getting the number in the post).
Getting a bank account was tricky though, most banks wanted a proof of address on a utility bill, but I couldn't sign up to sky/etc without a bank account. In the end, HSBC gave me an account with my passport as proof of who I said I was. Other than that, it was as difficult as moving city. Obviously not everyone has it this easy.
> I moved to the UK (from Ireland). It was relatively painless.
That's because both are EU countries (for now at least). Moving to France will also be much easier if you're an EU citizen, you won't have to deal with residence permits and your driver's license will also be valid.
You don't have to deal with residence permits but you will have to get a residence card, because without you will have lots of problems. Your driving licence is valid for one year, after that you have to convert your licence. Depending on what classes you have this will require medical tests and additional examinations.
It took me a month to get my NIN, which would have meant I wouldn't have been paid, and would have been unable to pay rent. (First job out of University).
None of the banks I spoke to (TSB, Santander, nationwide, RBS) would accept a letter from my employer
Getting a bank account was tricky though, most banks wanted a proof of address on a utility bill, but I couldn't sign up to sky/etc without a bank account. In the end, HSBC gave me an account with my passport as proof of who I said I was. Other than that, it was as difficult as moving city. Obviously not everyone has it this easy.