I sort of fell into this one.
The local photo lab still does traditional colour negative processing in 35mm and 120 but a couple of years back, knowing I did my own B&W, they asked if I'd be interested in processing any B&W film that comes in rather than them having to send it away at big cost and waiting time at a professional lab.
So I develop any traditional B&W film that comes in and give it back to them to do the printing just as they would if it was XP2.
I run an account with them. They credit the account for $10 per film and when I want something from them (usually the occasional colour print) then they just take it out of the account. Pocket money stuff, but helps keep me in chemicals and 'free' colour prints.
I have a friend who has set up in a semi-rural area to do photography for schools, fetes & fairs, churches, sporting clubs, local politicians etc. They're too far out of a big town for the regular photographers to bother but there are a lot of small schools and clubs in the wider district. Digital of course. He has everything set up in the back of a van with a Mac Powerbook, power supply from battery/inverter, generator or direct plug in and can do A3 colour prints on an Epson R2880, burn and print CD's etc on the spot. If his wife goes along he swaps out the memory cards in his camera quite often and she goes back to the van to do the editing while he continues to shoot. Uses two Canon DSLR's.
He has to do a lot of networking and marketing to get his name out there and get remembered but it seems to be working for him. But it's not all 9-5 or Monday to Friday. He works every weekend and a lot of nights at meetings etc.