Conjuguemos was started in 2000 by me, Alejandro Yegros, a Spanish teacher in Weston HS, (Weston, MA). I wasn't a fan of teaching verb conjugations and figured a computer program could do this task better than me and a bunch of worksheets. So I started CONJUGUEMOS as a hobby and have kept at it for many years. I still work in the same school, and over the years have helped teachers add a lot of content to this site.
This site has about 3.5 million registered users, and is used by hundreds of thousands of students a day to learn vebrs. It is a community-sourced site: almost all the activities were created by teachers around the country and world who have wanted to add to the site. Teachers approach me via the site, I make the computer code, and they provide the word lists. I would say that collaboration has been the highlight of the years working on this project.
If you're a long-timer user, drop me a note. This site has changed and grown tremendously over the years, and I'd be curious to hear what those who have gone through it think.