Back in the early 90s (whe the web was young) I had a GM that set up a directory on his PC with the files were were after during the run on it. It became a regular thing. Admitted, it was fairly primative since the wealth of images videos and such were not avaliable like they are today, but he did a really good job with it, including thing slike hidden files and directories, interesting dead ends (for instance, there was a hidden node of ASCII Art nudes), fake e-mails and a number of image files (he was a photographer and into image manipulation). He even had some files and directories password protected and others PGP encrypted to simulate ICe with dice rolls getting the password or keys.
Best one he did was he produced a rather large sound file that, when played to a modem (to, not through) decoded into a a neat text file that we needed. IIR, he got the idea from the Information Society album that did the same trick with a "hidden track."
These days it would look really primative, but back then it was extremely cool and "cutting edge." Unfortunately, hard disk limits meant he couldn't have a lot of them on his HD at any given time (usually 2 was his limit since he needed most of the drive for his schoolwork) and 1.44 meg floppies couldn't contain them, so they were deleted to make space for the next one.