Quite a few home
entertainment devices can be 'modified', allowing more
features then the
manufacturer intended. Do-it-yourself
hacks are also common --
mod chips can often be seen for sale on online
auction sites.
Before DVD players became common, circumventing copy protection in game consoles (playstation and dreamcast, for example) was the most widespread mod. The ability to play import games was also a big plus -- there are three times as many playstation games available in Japan than North America, for example.
DVD players are commonly sold modified, allowing one to bypass dvd region lockout.