Just so you guys know, Narbacular Drop was made by the Portal developers while they attended Digipen. (They are all now Valve employees).
Also
Aperture Science (Viral Portal Website)
The website, Aperture Science, is run by Valve and presents a Flash-based green monochrome computer terminal that visitors can interact with. To "login" to the terminal one must enter login, logon, user, list, or help, followed by any username and the password portal or portals. At this point several commands prompt results, such as thecakeisalie, dir, lib, ls, apply, logoff, and valve. Entering apply will take you to the questionnaire, while entering valve will take the user to the Steam website, or in some cases the users homepage.
A dark undertone to Portal is revealed in the application questionnaire (accessed when the user types APPLY at the B prompt after logging in with the password PORTAL) asks such questions as how much the applicant can withstand pain before passing out, how they would react to torture, if they felt anyone was watching them, how long they could stay awake; or "would anyone miss them" "if they were to disappear tomorrow", etc. There are a total of 54 pages in the questionnaire. The questionnaire ends chillingly with the user being told to wait at their workstation to be investigated by a superior after failing to properly enter a 64 digit ID code displayed before the questionnaire begins (which changes while displayed, making recital virtually impossible and the fact that the code is case sensitive and what the user types on the keyboard are all in capital letters). During the questionnaire, in some questions, the user can see letters dimming and (on one page) even see an ASCII art of a cake flash for a brief moment. By taking all the dimming letters in the questionnaire and arranging them in the order of appearance, it spells out THECAKEISALIE. Typing that at any time after login/after the questionnaire reveals a hidden message from a distraught employee and a security camera video, hinting that Aperture is not all it seems to be, with the final line, "I don't think going home is a part of our job description anymore", before telling the user to press return if a supervisor passes by (which brings up a fake spreadsheet software image. The spreadsheet lists a curious item, INTUB-XLG, of which one was ordered, costing $974,999.99. The only other things on the spreadsheet are 50 units of flour and 75 units of thumbtacks.) There is also an option to try to INTERROGATE an employee, but are rebuffed as not having clearance with an error message stating: "Illegal attempt to initiate disciplinary action". There are also bizarre questions, such as what wild animal the applicant would choose to domesticate, and what the applicant's favourite colour is (in a later question, the applicant is asked what their favourite colour is again, but the colour they previously chose is not present as an answer). Wikipedia.