I recently developed a Verilog Simulator for Windows-platform. It's called LogicSim and is free for the time being. It supports most of the Verilog-2001 constructs, and has a very good Verilog text editor and development environment. I'm currently in the process of adding a waveform editor, mixed-languages (VHDL, SystemVerilog, etc.), VPI/PLI and Linux support. I'd be glad if you can try it out and report any problems, bugs or requests to me. It can be downloaded atthanks.
Joe, LogicSim - Your Personal Verilog Simulator