collisions for md5:

# two distinct inputs which produce an identical hash value for the infamous (broken) md5 hash function, i.e., a collision:
echo d131dd02c5e6eec4693d9a0698aff95c2fcab58712467eab4004583eb8fb7f89 > 1.asc
echo d131dd02c5e6eec4693d9a0698aff95c2fcab50712467eab4004583eb8fb7f89 > 2.asc
echo 55ad340609f4b30283e488832571415a085125e8f7cdc99fd91dbdf280373c5b >> 1.asc
echo 55ad340609f4b30283e4888325f1415a085125e8f7cdc99fd91dbd7280373c5b >> 2.asc
echo d8823e3156348f5bae6dacd436c919c6dd53e2b487da03fd02396306d248cda0 >> 1.asc
echo d8823e3156348f5bae6dacd436c919c6dd53e23487da03fd02396306d248cda0 >> 2.asc
echo e99f33420f577ee8ce54b67080a80d1ec69821bcb6a8839396f9652b6ff72a70 >> 1.asc
echo e99f33420f577ee8ce54b67080280d1ec69821bcb6a8839396f965ab6ff72a70 >> 2.asc
xxd -r -p 1.asc > 1.bin
xxd -r -p 2.asc > 2.bin
if cmp -l 1.bin 2.bin;then echo the two files are identical...;else echo the two files are different;fi
md5sum 1.bin 2.bin
# the commands above result in the following remarkable output:
1.bin 2.bin differ:
 20 207   7
 46 161 361
 60 362 162
 84 264  64
110 250  50
124  53 253
the two files are different
79054025255fb1a26e4bc422aef54eb4  1.bin
79054025255fb1a26e4bc422aef54eb4  2.bin