If you can't wait until next month to start killing Russian terrorists then this is your lucky day. The Call of Duty 4 single player demo is online and available for download over at FileFront. Make sure to check the PC requirements and recommended specs for optimal gameplay after the jump.
Recommended system requirements
* CPU: 2.4 GHz dual core or better is recommended
* RAM: 1 GB for XP; 2 GB for Vista is recommended
* Harddrive: 8 GB of free hard drive space
* Video card: 3.0 Shader Support recommended. Nvidia Geforce 7800 or better or ATI Radeon X1800 or better
Minimum system requirements
* CPU: Intel® Pentium® 4 2.4 GHz or AMD® Athlon™ 64 2800+ processor or any 1.8Ghz Dual Core Processor or better supported
* RAM: 512 MB RAM (768 MB for Windows Vista)
* Harddrive: 8 GB of free hard drive space
* Video card (generic): NVIDIA® Geforce™ 6600 or better or ATI® Radeon® 9800Pro or better
link to download