GCC for Windows 64 & 32 bits
TBD
Rubenvb toolchains
Rubenvb has built a number of toolchains including some for less common setups. They are split into two categories: toolchains targeting Win32 or Win64.
OpenSUSE
The OpenSUSE Linux distribution also has a large and well-maintained set of packages for cross-compilation.
A very large number of other binaries and sources are hosted in the File Release System on Sourceforge which might have what you are after.