giffiltr(1) on Linux
The text 14d2cb38c2f4, as Debian 8 (Jessie), Debian 7 (Wheezy), Debian 6.0 (Squeeze) shipped it. The page shows this text now.
This is an expensive way to copy a GIF. The source is included as a skeleton for more sophisticated filters. See the source in the util directory for details. I suppose this does have some utility as a test of the sequential GIF record I/O routines. The output should be bytewise identical to the input.