Back during the early days of D&D 3rd edition WocT did experiment with digital RPG materials for their Alternity line of RPGs. The biggest of these experiments was the last product released for the line The Externals which introduced the start of a major war in the StarDrive setting. This product had a PDF of the book, a stardrive calculator to determine how many jumps it would take to go from any system in the Verge to another, and a browsable version of the book.
This browser based book was launched using Flashplayer which then launched your web browser and using flash allowed you to navigate to book as it was a web site. Sadly the browser part is no longer useable because it requires Flash but this video is how the launcher opened.
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