If you want to learn C#, you probably want to skip this, it has nothing that is important to you really, if you insist here you go.
A language that has a .NET compiler is a language where a compiler exists that can translate the language to IL rather than machine Code.
You probably already write one of these languages, (PHP is very popular and a .NET language…) see the list below
A#
APL
ASP.NET: ASM to IL
AsmL
ASP (Gotham)
Basic
-> VB .NET (Microsoft)
-> VB .NET (Mono)
BETA
Boo
BlueDragon
C
-> lcc
-> cscc
C#
-> C# (Microsoft)
-> C# (Mono)
Cw
C++ (Microsoft)
Cat
CIL
Cobol
-> NetCOBOL (Fujitsu)
-> Net Express (Micro Focus)
CQL
CULE.NET
E#
Eiffel
F#
Forth
Fortran
-> Fortran (Lahey)
-> Fortran (Silverfrost)
Haskell (VHS)
IronPython
Java
-> J# (Microsoft)
-> Java (IKVM .NET)
-> JNBridge
JScript .NET
Lego.NET
Lisp
-> DotLisp
-> IronScheme
-> L#
-> FOIL
leXico
LOLCODE
Lua.NET
M#
Mercury
Metaphor
MixNet
Mondrain
Nermerle
Oberon
Ook# .NET
OMeta#
Pan#
Pascal
-> Chrome
-> Delphi
-> Component Pascal
PerlNET
PHP
Prolog
Ruby
-> IronRuby
-> Ruby/.NET Bridge
-> Ruby.NET
Smalltalk
-> S#
-> #Smalltalk
-> Smalltalk and .NET
Scala
SML .NET
Spec#
Tachy
TickleSharp
Zonnon