Tools of the trade for myself (keep in mind I do 99% of my code cross-platform): Generally prefer Intel compilers, al though what I have licensed is highly out of date, so I generally fall back on the GCC platform. If I have the option to me, I use MSVC's cl on WinNT.
I prefer the Qt toolkit for GUI development, but have toyed around with GTK+ somewhat and was /not/ impressed.
I occasionally fiddle around in .NET, which I used to use heavily (especially at an old job), but really only use it for small Windows apps and Websites. I have used the Mono framework when porting one aspx app to GNU/Linux.
Occasionally I do daemons so I use straight C and occasionally GLib and Mowgli as a complement library.
I stay away from Java like it's aids, because it is. Win32 API doesn't appeal to me as well as a ton of other FOSS devs, due to the fact it's old and Microsoft has no plans on improving it or MFC.
Last, I do not use IDE's. Crimson Editor is my favorite tool.
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EFNet