Epiphan
I was looking for this for a while... I need to input power point presentations that clients want to operate themselves, without option to convert the content because they usually have it ready 1 hour before the show...
I tried the canopus twinpact100 but the delay on the firewire is a problem....
the best I've used are the epiphan USB2VGA units they have a wide range supporting different resolutions..
I use two of the LR version, 30fps, at 1280x1024 top resolution.
check www.epiphan.com
The will run you about U$800
[SIZE="1"]
1 Catalyst PM Pro V4.40 m466
-1 Mac Pro 3.0 Ghz Dual Quad Core Xeon
ATI Radeon XT1900 512 MB
16GB RAM
OSX 10.6.8
-1 MacBook Pro 2.7 Ghz Quad Core i7
Nvidia GeForce 8600M GT 256 MB
16GB RAM
OSX 10.8.5
-1 Matrox TH2G DP Edition
-1 Blackmagic Decklink Duo
-1 Epiphan VGA2USB LR
RoadHog 4