What is the state of the contract programming language LLL (Lisp-Like Language)? Is it still used and supported?
There does not appear to be active development on LLL as the Ethereum Foundation has identified Solidity as it's primary language that will receive development support from them. However, it is not "dead" in the sense that there are still bug fixes and small changes happening to the repository infrequently.
Interesting side note: Inline ASM may be eventually supported in the Solidity Ethereum language.
Vitalik Buterin said in Nov. 2015:
LLL was always meant to be very simple and minimalistic; essentially just a tiny wrapper over coding in ASM directly. In my opinion just use serpent; it has direct access to opcodes so it is a superset of LLL but it also has a whole bunch of high-level features as well for when you want them. The downside is that the compiler is more complex and so theoretically might contain more bugs.
If it's still used one can hardly tell. The last ethereum forum post to this topic is dated back to 2014.
While building the full C++ ethereum stack I noticed it contains
lll packages. There is
liblll for instance, which is still receiving commits. Last commit was back Sept/2015.
TL;DR: Used - hardly. Supported - certainly.