USB adapters with the
DisplayLink DL-195 Chipset should be able to run a second display through USB on Lion. There are DisplayLink beta
drivers for 10.7.3 and higher and even Mountain Lion. If you don't plan on running HD video or gaming on the monitor connected to this adapter you should be okay. The adapter uses the CPU to drive the display so there could be issues doing anything intensive.
I got one of these for driving my PA246Q, which will only be used for documents and mail.
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