All you Basic fans might like RealBasic. It has a beautiful IDE which IMO rivals all of the pro development environments (very similar to the one in Delphi 7 before they changed it), the code completion works properly, it has a powerful class system with many useful classes built in, and despite all those features it is still really easy to and the code is nice and readable.
Also, it can cross-compile for Windows, OS X and Linux.
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moto