I did this for an old, but still great game that I play from time to time. I had a really hard time finding a high resolution stock of the Enclave soldier's helmet, so bare with the quality will ya?
EDIT: 48x48 and under the icon will revert to a colored Enclave Head.
It's Vista ready and includes the following sizes: 16x16, 24x24, 32x32, 48x48 & 256x256(PNG Compressed) in RGBA (32 bits) & 256 (8 bits).
256x256 PNG file included for dock icons.