Various types of double exposure can be done by PhotoShop software.
Example:
http://www.pbase.com/markl3755/image/34978928
Here is a thread from a Digital Rebel forum on the subject of double exposure: Read all the links in the thread.
http://forums.dpreview.com/forums/read.asp?forum=1031&message=6005666
Instant Shots:
Not such a simple subject since autofocus is dependent upon the lens used.
Here is a page from a Rebel review:
http://www.steves-digicams.com/2003_reviews/300d_pg6.html
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I have a Sony 717 that needs to be replaced. The camera was a lot of fun to use, but I missed the flexability of my old Ricoh 35mm SLR. The focal length is better on the 828, but the Rebel will host a wide array of lenses, at additional costs. Will the Canon give me the instant shot that my 35mm used to offer? I used to like playing with double exposures with the Ricoh, will any digital have such effects.

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