Currently, a paid Unity license can be activated on two computers. This isn't enough for the needs of a modern developer targeting multiple platforms. Granted, a limit of two activations is common for software licenses in general. This is under the assumption that the end-user has one desktop computer and one laptop computer, and needs to activate the software on each. However, cross-platform development with Unity often requires the developer to utilize both Windows and Mac computers. For example, I have a Windows desktop for primary development, a Windows laptop for when I'm out of the office, and a Mac Mini for when I need to make and test an iOS or OSX build. With the current two-activation limit, I can't use my license on all three systems at once, which means I need to deactivate the laptop and activate the Mac when I'm in the office, and deactivate the Mac and activate the laptop when I'm out of the office. Unity licenses should support three activations, or have separate limits for OSX and Windows activations, so that cross-platform developers can utilize multiple computers without having to jump through hoops.