| The T52 Sturgeon Challenge — Part 3 | 1,124 | Nov. 13, 2021, 11:14 p.m. |
| The T52 Sturgeon Challenge — Part 2 | 1,164 | June 4, 2020, 12:23 p.m. |
| The T52 Sturgeon Challenge — Part 1 | 1,163 | June 2, 2020, 10:56 p.m. |
| Cracking SHA1-Hashed Passwords | 1,101 | Jan. 10, 2016, 7:52 a.m. |
| ORYX Stream Cipher Part II | 1,150 | Dec. 20, 2011, 4:04 p.m. |
| Lattice Part 1 | 1,613 | March 15, 2011, 7:28 p.m. |
| CMEA 1 | 1,286 | Jan. 24, 2011, 10:53 a.m. |
| ORYX Stream Cipher Part I | 1,231 | Jan. 21, 2011, 5:39 p.m. |
| A modified homophonic cipher with reduced alphabets — Part 2 | 150 | Oct. 23, 2010, 12:17 a.m. |
| A modified homophonic cipher with reduced alphabets — Part 1 | 150 | Oct. 22, 2010, 10:43 p.m. |
| Not-so-Secret Message from Malawi — Part I (RSA) | 1,576 | Oct. 19, 2010, 10:44 p.m. |
| A Secret Message from Castle Mansfeld | 200 | Oct. 14, 2010, 1:36 p.m. |
| Monoalphabetic Substitution | 200 | Oct. 14, 2010, 1:35 p.m. |
| Alice's Birthday Party (Part 2) | 2,000 | Oct. 14, 2010, 1:31 p.m. |
| Alice's Birthday Party (Part 1) | 2,000 | Oct. 14, 2010, 1:30 p.m. |