| Letter to the Templars — Part 1 | 200 | July 17, 2012, 12:37 a.m. |
| Grille Cipher | 150 | Oct. 15, 2011, 11:49 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,159 | Oct. 3, 2011, 12:18 a.m. |
| Pigpen with a twist — Part 1 | 125 | Sept. 9, 2011, 6:02 p.m. |
| A really long number sequence | 1,725 | Sept. 8, 2011, 6:15 p.m. |
| Brute-Force-Attack on Triple-DES with Reduced Key Space | 1,165 | Aug. 21, 2011, 12:49 a.m. |
| ADFGVX — Part 1 | 120 | Aug. 20, 2011, 12:16 a.m. |
| RSA: Two different keys — same ciphertext | 2,000 | Aug. 16, 2011, 2:55 a.m. |
| Alice's Birthday Party (Part 2) | 1,167 | Aug. 9, 2011, 10:51 a.m. |
| Alice's Birthday Party (Part 1) | 1,167 | Aug. 9, 2011, 10:17 a.m. |
| Broadcasting and low exponent — RSA Attack | 1,398 | Aug. 9, 2011, 9:24 a.m. |
| Monoalphabetic Substitution | 100 | July 30, 2011, 10:49 p.m. |
| Classical Ciphers^3 | 100 | July 29, 2011, 11:42 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 100 | July 27, 2011, 11:08 p.m. |