• D. J. Bernstein's home page.
• The qmail home page.
• The djbdns home page.
• The daemontools home page.
• The ucspi-tcp home page.
• The cryptography page.
• United Airlines sucks (part 40).

Some popular subdomains of cr.yp.to:

• NaCl, the Networking and Cryptography library.
• ECRYPT benchmarking.
• the Bernstein v. United States page.

Some popular links outside cr.yp.to:

• DNSCurve.
• EFD, the Explicit-Formulas Database.
• Post-quantum cryptography.
• RITES, UIC's Center for Research and Instruction in Technologies for Electronic Security.