I have written a prototype tool that is similar in spirit, and in some 
of its workings, to QuickCheck,
but based on exhaustive testing in a bounded space of test values.  
Sales pitch: wouldn't you like to ...
* write test generators for your own types more easily?
* be sure that any counter-examples found are minimal? (##)
* write properties using existentials as well as universals?
* establish complete coverage of a defined test-space?
* display counter-examples of functional type? (##)
* guarantee repeatable test results? (##)
For more details and a Haskell 98 module SmallCheck download the small 
tar file at:
http://www.cs.york.ac.uk/fp/smallcheck0.0.tar
If you try it, do let me know how you get on.  Comments & suggestions 
welcome.
Colin R
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(##) There have been versions of QuickCheck with extras that address 
these issues in other ways.