Is there an FOSS alternative to LinqPad with any of the same features? I'd prefer to support open source but if non-free software's much better I'll probably just go with that.
Well, scriptcs sounds somewhat analogous. Similar REPL for C#, allows for packaged scripts, plays nicer with the filesystem than an IDE (which you'd expect for command-line apps). http://scriptcs.net/
Note: I've tried to use scriptcs, but the extent of my C# knowledge consists of pretending it's Java. But people do seem to compare it to LINQPad, so maybe it fits.
Linqpad's amazing "dump" isn't to be found in scriptcs or anywhere else, so far as I'm aware, however. Which really does make working with a C# REPL a million times nicer.
Note: I've tried to use scriptcs, but the extent of my C# knowledge consists of pretending it's Java. But people do seem to compare it to LINQPad, so maybe it fits.