Takes as input the specification of a finitely-valued first-order logic and produces a sequent calculus, a natural deduction system, and clause formation rules for this logic.
http://www.logic.at/multlog/
A semi-automated system for the verification of statements about programs written in a functional programming language. The system is capable of following fully-automated routines for theorem proving and hypotheses formation, as well as operating interactively when these reoutines fail.
http://www.informatik.tu-darmstadt.de/pm/verifun/
A graphical IDE for creating, running and debugging Turing machines. Freeware for Windows 95/98/NT/2000.
http://www.cheransoft.com/vturing/
WinKE is an interactive proof assistant based on analytic tableaux, and designed for the teaching of deductive reasoning. Ordering information is available at this site, as are academic papers on the design of the software.
http://www.dcs.kcl.ac.uk/staff/endriss/WinKE/
Program understands the different types of lambda expressions, can extract lists of variables (both free and bound) and subterms, and can simplify complicated expressions. Uses Python.
http://www.alcyone.com/software/church/
Deals with effectively machine-checked formal mathematics. In practice, this includes the study of mathematical formalisms well-suited for implementations, the implementations themselves and the use of these for various applications. Focuses on software correctness proofs.
http://pauillac.inria.fr/coq/
First-order satisfiability checker and prover for the Macintosh.
http://www.humnet.ucla.edu/humnet/phil/grads/herzberg/Bertrand.html
Manual
http://margo.student.utwente.nl/el/cad-cam/mini450.txt