Presentation remote for iOS, Mac and PC?

I'm a psychology instructor at a community college. Sometimes I feel like using Keynote on my iPad or Macbook, and other times I feel like using PowerPoint on the school's PC. It just depends what my lecture entails and PowerPoint handles some things differently than Keynote and the OS makes a huge difference. I want to be able to control my presentation with a remote that I can use on all devices. (Not all at once, of course.)
Problem is the PC in the lecture auditorium does not have bluetooth. I found this remote and I think it is perfect, but it doesn't have a USB adapter for the PC and I'm not sure if it is PC compatible.http://www.satechi.net/index.php/ipad-iphone/satechi-bluetooth-smart-pointer-mobile-presenter-and-remote-silver-control-for-iphone-ipad-ipod-touch-samsung-galaxy-s3-note-2-imac-macbook-air-macbook-pro-macbook-and-mac-mini
I like Apple's Keynote Remote for the iPhone, but it doesn't have a laser feature.

I was going to recommend something more along the lines of this Targus remote, but I'm a little surprised by the reviews. I've had various Targus remotes over the years and have had no problems.

http://www.targus.com/us/productdetail.aspx?sku=AMP13US

I'd recommend it because…

1) good form-factor
2) USB - so it will work with any computer
3) has a laser pointer
4) has a space to store the receiver piece
5) runs on standard batteries - so no chasing down weird watch batteries when these die