I've created this (hopefully) easy-to-use sociotypograph, which allows to determine a person's sociotype by selecting 3 or 4 of Reinin traits, they surely have. One can also use it to look up a sociotype's traits.
Take it for a spin and please let me know what you think, or if you find any mistakes.
If you really like it and would like to get involved: I'm looking for a designer, mobile app developer and copywriter/editor/proof-reader.
Added: also see sindri's dichotomy calculator