Sometimes called cross-processing, which is not entirely accurate, because this term means something a bit different. Nonetheless, the development of color film negatives as black & white is a good experience, is fun, and it gets one out of that odd spot of trouble. I myself have no option to develop color; I used to, a long time ago, and I graciously (and cowardly) gave up. Main reason being maintaining the temperature of the tank/solutions. The grain was the size of gravel, and it was too cumbersome an operation for me at least.
Anyways, I still have a lot of color rolls in my fridge, mainly Kodak Ektar 100 and Fuji Superia in both 100 and 400 (35mm), some 120 Portra, quite a number of generic 200 ASA, and a few bulk rolls of Kodak 16mm. As my local c41 lab closed its doors a few years ago, I have no choice of processing this color stock anywhere. Therefore, I will cut it, slice it, use it, scan it as BW instead of color. It'll be an interesting year :).