GTKWave is a fully featured GTK+ based wave viewer for Unix, Win32, and Mac OSX which reads LXT, LXT2, VZT, FST, and GHW files as well as standard Verilog VCD/EVCD files and allows their viewing. You can grab version 3.3.61 here. Documentation in pdf format can be found here.
The Win32 version is available here,
however if you are running Cygwin, running under that is recommended instead.
A Mac port can be found both here and here. A ready to use Quartz (not X11) App bundle for x86_64 can be found here.
Ports to other platforms which GTK supports should be trivial.