Can’t find it anymore but there was a whole wiki page on what Turing machines you could have. I once was working with an xml-like language and asking myself if

Can’t find it anymore but there was a whole wiki page on what Turing machines you could have. I once was working with an xml-like language and asking myself if it was turing complete. You could create scores in that language which were basically integer variables. The trick is to then only have 0 and 1 as a valid alphabet. That meant that an integer can be represented as a stack of 0’s and 1’s. Add another integer and now you have two stacks. You could also make a Turing Machine just by using prime numbers.