Safalra
Safalra is the pseudonym of British computer scientist, erstwhile mathematician and occasional philosopher Stephen Morley. He prefers to be known by the pseudonym due to the existence of various other people called Stephen Morley (including a mathematics professor).
Safalra first became interested in esoteric programming languages after reading the INTERCAL entry in The Jargon File. After discovering Georg Kraml's now-defunct database of esoteric programming languages he created the Sansism and MISC languages.
In 2005 Safalra created the Gravity language to show that a language that cannot be simulated on a Turing machine can be proved Turing-complete. The mathematics this entails are complex, and so far the proof has not been forthcoming, although some simple programs have been produced.
Safalra has contributed to the Esolang Wiki as User:Safalra, but not since 2006. He has created proofs of Turing-completeness for a number of languages, and has translated the German specification of the AlPhAbEt language.
Safalra was, in 2005, in the process of writing online interpreters in Javascript for a number of esoteric programming languages. So far he has written interpreters for HQ9 Plus, HQ9 Plus Plus, NIL, Qdeql and Smurf.