I guess you are done with Caesar I, aren't you?
The big problem with caesar is that it does not allow digits or other characters.
I have fixed this, and now I can use any ascii character in the plaintext.
The keyspace has increased from 26 to 128 too. \o/

Enjoy!

17 3F 3F 34 20 3A 3F 32 7C 20 49 3F 45 20 43 3F
3C 46 35 34 20 3F 3E 35 20 3D 3F 42 35 20 33 38
31 3C 3C 35 3E 37 35 20 39 3E 20 49 3F 45 42 20
3A 3F 45 42 3E 35 49 7E 20 24 38 39 43 20 3F 3E
35 20 47 31 43 20 36 31 39 42 3C 49 20 35 31 43
49 20 44 3F 20 33 42 31 33 3B 7E 20 27 31 43 3E
77 44 20 39 44 0F 20 01 02 08 20 3B 35 49 43 20
39 43 20 31 20 41 45 39 44 35 20 43 3D 31 3C 3C
20 3B 35 49 43 40 31 33 35 7C 20 43 3F 20 39 44
20 43 38 3F 45 3C 34 3E 77 44 20 38 31 46 35 20
44 31 3B 35 3E 20 49 3F 45 20 44 3F 3F 20 3C 3F
3E 37 20 44 3F 20 34 35 33 42 49 40 44 20 44 38
39 43 20 3D 35 43 43 31 37 35 7E 20 27 35 3C 3C
20 34 3F 3E 35 7C 20 49 3F 45 42 20 43 3F 3C 45
44 39 3F 3E 20 39 43 20 3D 3D 36 34 3D 38 3E 32
32 35 31 36 7E