Here is a brief list of science-related sites that run on the same platform as Math Overflow: - Science - [Science Stack][1] - [asksci.com][2] - Physics - [physics.stackexchange.com][3] - [PhysicsOverflow][16] - Electronics - [Electronics Exchange][4] - Programming - [Stack Overflow][5] A complete list of these sites is available [here][6]. The one thing that I personally feel is missing is a lower-level mathematics site (a Math Underflow, if you will). I understand the desire to keep Math Overflow relevant and interesting for professional mathematicians, but there is currently no equivalent site for amateurs and students. **Update:** (Sept 2010)A math site for [university level mathematics exists now][7]. There are also sites for [theoretical computer science][8] and for [statistics][9]. (April 2011) There is a [TEX Q/A site][10]! (September 2011) [Area 51: science][11] contains new proposed stackexchange sites related to science. We can mention especially proposals for [Theoretical physics (and mathematical physics)][12] (closed), economics (closed), research economics, game theory, [computational sciences][13], [philosophy][14] (the site is running), [numerical models and simulations][15], Mathematica, mathematics in german. [1]: http://sciencestack.com/ [2]: http://asksci.com/ [3]: http://physics.stackexchange.com/ [4]: http://electronics.stackexchange.com/ [5]: http://stackoverflow.com/ [6]: https://meta.stackexchange.com/questions/4/list-of-stackexchange-sites/5#5 [7]: https://math.stackexchange.com/ [8]: http://cstheory.stackexchange.com/ [9]: http://stats.stackexchange.com/ [10]: http://tex.stackexchange.com/ [11]: http://area51.stackexchange.com/categories/7/science [12]: http://area51.stackexchange.com/proposals/23848/theoretical-physics [13]: http://scicomp.stackexchange.com/ [14]: http://philosophy.stackexchange.com/ [15]: http://area51.stackexchange.com/proposals/1907/numerical-modeling-and-simulation [16]: http://physicsoverflow.org/