I made this b/c a single typeracer tab on chrome was using over 500 MB of RAM and I also noticed latency.
I tested BrightType on an old laptop w/ 2 GB RAM, an HDD, & a slow CPU, and the typing experience is still smooth. If only I was born 30 years earlier... BrightType would have been so popular.
Minimum supported OS: Windows Vista (with Service Pack 2 and Platform Update) and above.
*Unfortunately, my app is not cross-platform b/c I developed it w/ Win32.
Minimum Hardware: 64 MB of RAM, 2 MB of free disk space, and a keyboard.