Last year we did some work in Mono together with Luis Ortiz to support 64-bit arrays in the VM.
What was interesting about this work is that even though the ECMA standard allows the index of arrays to be a long .NET on Windows64 does not support this and Java would require modifications to the bytecode format. Altering Mono became the natural choice for those looking to host very large arrays in an advanced and managed VM.
This means that you can continue to use your existing tools to build applications, but when running under Mono you will get to use those arrays without that pesky 2,147,483,648 upper boundary.
SiCortex has an entry-level desktop computer with 72 MIPS processors and if you have the budget you can get modules with 5,832 processors. The MIPS processors helps them stay eco-friendly.