While I'm not sure what application this could be, the usual is to use a YMOUSE you can find at http://www.google.com/search?&q=YMOUSE
for a specific application package i just got i need to have 2 mice connected to my home pc. they must be manually switchable from one to the other. i thought this will be a no-brainer, but i guess i was wrong. all i can find is kvm switches. i want to plug in 2 (usb or ps/2) mice and flip a switch to decide which i will use.