"Lines of C" is an arbitrary and relatively meaningless metric. Even number of characters would have more meaning and perhaps be more interesting than number of 'lines'. Unless you define a "line" as 80 characters (in which case you really have a rough estimation of character count).

Nonetheless, these things are fun and often novel, both in what they accomplish and how they accomplish it. I like looking at them (not always reading them) for many of the same reasons I like looking at brainfuck or perl code. Plus, you know, compression. ;)