The Gender Genie website says it can tell your gender based on a sample of your writing.
I tried it with some old posts from this blog, and they all came out male, which is right. Then I tried it with some newer posts from another blog I write, and they all came out female. Seems like it has more to do with writing style than gender. In particular, there are certain words that they say are "female" words, and certain words are "male" words.
And they're not talking about "flowers" and "cars", but words like "if" and "a". Yes, strangely enough, the use of proper grammar and including all the articles of speech can affect your gender. At least, it can affect what gender Gender Genie thinks you are.
Part of the problem with systems like this is that the words chosen as "female" and "male" were made by analyzing the writing of men and women, and then running the words they use through a magic computer blender to see which words were gender specific.
But that sort of technique doesn't cross educational and cultural divides well, or even deal well with people who are into different hobbies than the original population.
The Gender Genie would be a lot more useful if they had the option to correct the system's prediction and feed that back into the calculations, so it could become more accurate over time and adjust to changing cultural and societal influences.
Or maybe it's just an interesting waste of a few minutes. Either way, have fun with it!