OpenDylan (http://opendylan.org http://opendylan.org) has been using MPS since MPS was first created. (Both were created at the now defunct Harlequin.) We've b

OpenDylan (http://opendylan.org http://opendylan.org) has been using MPS since MPS was first created. (Both were created at the now defunct Harlequin.) We've been working on reviving OpenDylan over the last year as well and this MPS update is a big boon for us.