This is the kinda topic I like. Watched something on Vimeo like your example photos recently, stunning technique when used right: http://vimeo.com/149046328
If one has to shoot a lot of "prismatic" imagery, it is probably easiest to use a prism camera filter. Here is an EOSHD article that features a few of these filters. Here are a few photos shot through prism/prism-filters. This page names different types of prism filters and gives tips regarding depth-of-field, subject distance and sandwiching filters.
The look of the images that the OP posted could probably be achieved with a linear prism filter -- if it weren't for the oddly placed window pane overlapping in the foreground.
Mirrors could be used, but they are much more of an involved set-up. Unless one wants a kaleidoscopic effect, one would probably shoot away from the subject, into adjacent/overlapping mirrors that reflect images of the subject. To recreate something similar to the oddly-placed, overlapping window-pane image, a piece of clear glass could be positioned at an odd angle in front of the mirrors. By the way, front-surface mirrors will give more clarity than normal mirrors, but, of course, front-surface mirrors are rarer.
