Q:

What are the results of developing slide film (E-6 process) with C41 chemicals?

I recently got hand on some rolls of 35mm slide film (Kodak Ektachrome), and was planning on developing them at home (bad experiences with photo labs).
On a basis of budget, I wanted to develop them along with my other C41 rolls,
so that I wouldn't have to buy two sets of chemicals.
So...
1) Will E6 rolls develop with C41 chemicals?
2) What kind of results should I be expecting? (Colors, physical film properties, etc).
Disclaimer: I am aware that they probably won't be properly developed, but I am also aware of techniques such as caffenol which I find quite acceptable, in terms of results.

A:

I worked in a professional photo lab for a number of years. Cross Processing was something that guys like Scott Clum and Trevor Graves were using for their photography back in the pioneering days of snowboarding. The effect produced is very striking. 
The most common characteristics of cross processing is contrast and extreme color crossovers. Crossovers are color shifts that can't be corrected out of an image by normal means. For instance, an image might have a strong blue cast in the shadows but a heavy yellow cast in the highlights. Since blue and yellow are opposites (roughly speaking) if you attempt to correct out the blue cast in the shadows it only intensifies the yellow problem in the highlights. Although this image was manipulated in photoshop to achieve the effect it is a good example. Cred: basic clothing basica cross processing

On one occasion I inadvertently cross processed several rolls of E6 in the C41. It was a busy day and I simply walked to the wrong processor. I was mortified because the images were of a gentleman's mission trip to a remote part of the world. I was sick to my stomach. We ended up shooting copy slides and essentially re-cross processing the images. While it wasn't perfect the customer felt we had done our best.
If you decide to cross process be warned that getting reliable results in a positive image form are hard to achieve. Scanners and printers (as in photo lab printers) are designed to work with a negative that has a strong 'orange' substrate. Cross processing renders a negative without this baseline and the equipment rarely knows how to handle the extreme difference.
Have fun! Cross processing is a blast.

A:

Yes it is possible, and this is referred to as "Cross Processing"
Regarding the expected results, there is a good quote from wikipedia.

Cross processing
It is also possible to cross-process
  slide film for the E-6 process in C-41
  , which yields negatives with a color
  shift and stronger saturation. (C-41
  also may be processed in E-6 yielding
  positive images with a strong green
  cast, caused by the orange mask.)
  Varying brands and film speeds yield
  different color shifts producing
  bright, saturated colors and high
  contrast. Many modern digital
  mini-labs will produce unsatisfactory
  results when presented cross-processed
  E-6 as the scanner will attempt color
  correction to "normalize" the final
  image; this can generally be overcome
  by using professional dedicated film
  scanners and disabling any color
  correction if scans or prints are to
  be made. C-41 film can be processed in
  standard black and white chemicals, to
  produce a monochrome negative image.
  The negatives will typically be of
  very low contrast, and cloudy, partly
  caused by the orange mask.

