I'm a historian and linguist. I edit and create Wikipedia articles as a way of building up my knowledge of topics I plan to write about: it'll usually be food history, language history, and ancient and medieval people. I am an Interwikipedian: I have so far begun Wikipedia articles in about 12 languages and I have made worthwhile improvements (I think) to articles in over 30 languages. I now work most often on the Latin Vicipaedia, which attained its 80,000th article in October 2012 and its 100,000th article in December 18th 2013, but I'm around here regularly too.
I've also written about Wikipedia: see The World and Wikipedia. The book credits some 220 Wikipedia editors (and most of them for the best possible reasons): see Editors whose work is mentioned in the book. The English Wikipedia is a great achievement, but I believe what the Wikipedias have done for speakers of other languages is even greater.
Some have asked about the languages I know (or have begun to know), so here's a kind of answer. I don't claim to be a great linguist: if I have a skill in this area, it's simply that languages don't frighten me. I was at Bristol Grammar School, where I learned some Latin, French and Greek; then at the University of Cambridge. There I studied Latin and Greek at first, afterwards Romance languages and linguistics. I got a bachelor's degree in 1970. I gained familiarity with some other languages because of my work at Cambridge University Library, where I worked with foreign serials and afterwards with South and Southeast Asian materials. To help me with this -- I didn't know any of the languages in advance -- I took classes in Cambridge again (in Sanskrit, Hindi and Pali) and in London (in Burmese and Thai). I never got far with the last two because I didn't remain in the Oriental field for long enough. I did a part-time Ph.D. in ancient history at Birkbeck College London (in 1987-93), which improved my Latin and Greek. Living in France makes me go on learning French, and Wikipedia and my writing keep me in practice with other languages.
If you like, or don't like, what I write, welcome to my talk page, User talk:Andrew Dalby. You can even E-mail this user if you like. Here's a list, not complete, of my publications. Here are some Wikipedia shortcuts and statistics that I find useful.
Added in 2016: I still contribute most often on the Latin Vicipaedia. Which is a more useful resource than might be thought. Latin's a working language only for a fairly small number of people (and not many of those people use Vicipaedia yet) but it is a language in which hundreds of thousands of things are officially named, from new living species to topographic features on planets. Latin names are copied from Vicipaedia far across the Web, so it's good if we get them right, define them accurately, and link them to all the other languages people use. Plenty of work there ...
Is fearr leis an úsáideoir seo an ponc séiṁiṫe a úsáid in áit an litir h mar séiṁiú. This user prefers to use the dot above instead of the letter h as séiṁiú.