[throwaway7645]

The APL family of languages that currently have commercial implementations like Dyalog and Q w/ kdb+ database. J and GNU APL are both free & open source. Dyalog is nice though even though a commercial license sets you back a grand per year (basically what most C# users pay for VS). You get a nice interpreter, support, built-in graphics, full .NET interop, full R interop, heck even DDE which is still useful in finance and my own industry. They seem to take documentation really seriously and have pretty interesting conferences. I don't code in APL, but am considering it as their product just seems pretty agile for my needs (personal user productivity). Q is extremely expensive and is the APL derived language that accompanies the kdb+ database used for time-series analysis on stock quotes...etc. It was built by Arthur Whitney and legend has it the entire source code is 5 pages of C (being an APL guy he has it all scrunched up though...doesn't like to scroll). People seem to like it and be willing to pay a fortune.