A downloadable game for Windows
Meet Gray - an unbearably cute and insanely smart alien. Follow his unfortunate excursion to Planet Earth. Help him conquer Earth. "Gray" is a retro adventure game -- a classic point&clicker with 320x240 graphics in 4C (four colors!), with mesmerizing original soundtrack, lots of crazy dialogues, informative monologues, ridiculous riddles, snide humor, useless trivia, occasional vandalism and good ol' pixel hunting.
Unpack the Gray.rar file (using Winrar, Winzip or some such). Go to the extracted folder. Run Gray.exe to play the game. In case of trouble -- such as the game failing to initialize or giving you a blank screen -- run winsetup and run the game in windowed mode (check the box in the top left corner) and/or choose a "Graphic filter" (2x or 3x or 4x, depending on your monitor's native resolution). Readme file also contains some basic hints. It is possible, however, that the game won't be able to run on newer systems (Win 8 and up) -- and your super-duper graphic adapter might frown upon the game's native resolution of 320 by 240 pixels (which stopped being a standard over 20 years ago).
Fingers crossed, though!