One of the first computer games I was introduced to as a child was Nibbles. A Dos based snake game. Ok, it wasn’t the first one I remember playing. That was hangman on Spectrum, which my parents had programmed to contain the names of all the My Little Ponies.
Anyway, I have spent years trying to find an online version of Nibbles, no luck so far, other snake type games are just not the same. However I did find this site; DosGamesArchive which has a number of old Dos games that you can download, including Nibbles. The only problem with this is that my computer is too fast to run it, oh well. I will keep looking. Though while I was looking for Nibbles I did discover that they have another of my favourite childhood games; Secret Agent Man, commonly abbreviated to SAM. You play the role of a secret agent, number 006 1/2, and then fight your way past guards, robots and other obstacles to destroy the enemies radar. Skippy seems to think that this XKCD cartoon is appropriate at the moment;