ECDSA threshold signing I searched "ECDSA threshold signing" recently and found a lot of papers where it is said that their authors solved the problem of ECDSA threshold signing efficiently: e.g. here  and here. Why there are no practical implementations of those (e.g. in cryptocurrencies)?
I just saw this question now. There is no reference implementation of the 2-party threshold ECDSA protocol since this was joint work with Unbound Tech (previously Dyadic Security), and they did the implementation. In general, I am a strong proponent of open source, and all pure academic work that I do is published with open source code (see https://github.com/cryptobiu). However, in some cases, research is carried out in collaboration with industry, and where they do the implementation it is limited by them. I believe that this is a reasonable balance.

Note that Unbound Tech does have a commercial offering using this for protecting cryptocurrencies (but at the level of enterprises, and not individual wallets).