I didn't know HyperNext Studio at all. A HyperCard clone for Mac, with which you can also create Windows applications. However, the last version is a bit older, I don't know if it still runs with Lion. Meanwhile, it is freeware (though closed source, I guess because their last version is already a bit older). And also interesting: it offers two languages, one that is modeled after HyperTalk and RBScript, an object-oriented Basic from Realbasic (another IDE for OSX and Windows). I guess HyperNext itself might be programmed with Realbasic. Oh, and with the HyperNext Android Creator you can also build Android applications with HyperNext. The Android Creator is however paid (but not really expensive with 60 dollars). And unfortunately, it is only available for Windows, not for the Mac. Update: those who have Lion can forget about playing with HyperNext Studio, because it is PowerPC code, and there is no Rosetta in Lion. So the maximum OSX version is Snow Leopard.