Besides Frege, Haskell does indeed run on the JVM now via GHCVM [1] - it was my HSoC project. I'll be doing a release in a couple days once I get a couple issues sorted out and the installation is streamlined. I'm currently working with Cary Robbins on getting the HaskForce Intellij Plugin working for GHCVM. If all goes well, GHCVM 0.0.1 will ship with ghcvm, ghcvm-pkg, cabalvm (a fork of cabal-install
1.22.9.0/Cabal 1.22.8.0 that supports GHCVM), a working Intellij plugin, and will support all of GHC 7.10.3 extensions other than Template Haskell + interoperation with Java libraries. You can join us on Gitter for live updates [2].