Depending on your lab it can be tough (and expensive) to get your photos cross-processed, but I've found the secret to wicked cross-processed photos.
My first X-pro.
If your local professional lab is anything like mine, they charge an arm and a leg for anything, and add on charges for anything else – cross processing will cost you, pushing or pulling a film is another surcharge, and they’re already pretty expensive, wouldn’t it be great if your local department store could develop your lomography slide film?
Well, the secret is they can, they just don’t really know it.
You see, most cheap photo labs only have machines to develop C-41 film, so there’s no way they can do anything but cross-process slide film. If you give them slide film, they can only cross-process it.
If you come in with a single canister of 35mm slide film, they might warn you that the colours might come out a bit funky if you develop your film there, just say that’s fine, you’ve developed film there before and you liked the way it turned out (even if it’s not true, it helps!) If you’re a paying customer they won’t refuse!
Other secrets include befriending the staff, offering to pay beforehand (so you’ve paid, even if the photos don’t turn out), saying that you spoke to ‘the other guy’ before and they were fine with it, or just be honest and say you want to see how the photos turn out.
A little warning though, don’t do this with black and white film! A roll of black and white film that isn’t C-41 will come out blank is you put it through a C-41 development! And you don’t want that!