Project ideas?

Question

I've made (and posted) a Pig Latin translator and Caesar Cipher and I'm wondering if anyone knows any other cryptology encryptions or made up languages to code a translator for? I know I can look it up but I'd rather take suggestions

Answer 1

Maybe a Caesar Cipher with numbers?
input: abc789
shift: 2
output: cde901

Answer 2

Maybe text to binary converter?
To add to this, shorten the binary like so:
11100111 -> 312031
3 1's, 2 0's, 3 1's :)

Answer 3

a rsa coder for websites?

Answer 4

If you're interested, I've made a very simple encryption and decryption python program:
>>https://code.sololearn.com/cGYCD5u06lwB/?ref=app
>>https://code.sololearn.com/c35YB8jPl23H/?ref=app