1       base math
2       ASCII, Base64
3       Application protocols 1
4       MIME
5       PCAP files and Wireshark
6       Application protocols 2
7       IP, TCP
8       XOR masks
10      Examine pcap
20      Reconstruct image from HTTP in pcap
30      Reconstruct image from FTP in pcap
100     Hex decode
200     Base64 decode
250     Pull email out of pcap
300     More pulling things out of pcap
400     Still more pulling things out of pcap
700	Base64, then xor
800     DNS packet; you're going to have to do some research
1000    16-byte xor key, but can be obtained with 1-byte
1200    Another 16-byte xor key, can't be obtained with 1-byte
2000    Paul's covert channel thingy
3000    ICMP tunnel
5000    ICMP tunnel, with xor
25000   ICMP tunnel, with xor, multiplexed transfers