Ergo, the only way to do multiple displays is to have Apple's Thunderbolt display (which has the TB daisy-chain port) and then have an adapter (or just another display) on that. All adapters for other display plugs that are currently (August 2011) sold are mini DisplayPort, not Thunderbolt, so they'll end the chain. Remember, though, that all items on the Thunderbolt chain must be Thunderbolt devices until you get to the last item, which can be mini DisplayPort (this is because TB devices have a daisy-chain port DisplayPort devices are not required to). If you have discrete graphics in addition to the Intel integrated graphics (as found on the 15' and 17' MacBook Pro models), you can attach multiple monitors even if you have only one Thunderbolt port. If you have Intel's graphics only (the Intel HD Graphics), as found in the 13' MacBook Pro (and the MacBook Air and some Mac minis), you can attach one monitor to the Thunderbolt/mini DisplayPort port. Does it have one or two Thunderbolt ports?.Does your MBP have Intel integrated graphics or one of the nicer discrete graphics chips?.Two important things will dictate if an arbitrary MacBook Pro will support two monitors: You may also want to check the current status of Lion support, as I remember seeing some posts about bugs relating to DisplayLink adapters - they may have been fixed by now however.

This does allow you to use your existing monitors, and at relatively modest expense. Because of the limitations of USB, it's not a high performance solution - don't expect to do any gaming on it.

DisplayLink is essentially basic graphics card connected to your computer via USB. You can use one display directly connected to the Thunderbolt/Mini Displayport with an mDP-HDMI adapter, and run the second one with a DisplayLink adapter. not the 13' MacBook Pro or any MacBook Air, nor the base Mini). This only works on Thunderbolt equipped Macs with a discrete graphics card (i.e. Obvious drawbacks are the cost, and not being able to use your existing displays. This is the least flexible, but highest performing solution. You've pretty much got two options for two external monitors on a MacBook Pro:

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