There's also the question regarding the word "building"... Once the construction is completed, it's no longer in the process of being built so the "-ing" suffix is misleading. One might assume "built" would be the term to use. Taking into consideration entropy, wouldn't it be more appropriate to call it "crumbling?"

And then there are these:
CRT tube (Cathode Ray Tube tube).
ATM machine (Automated Teller Machine machine)
The La Brea Tar Pits ("La Brea" translates as "The Tar" -- so we're saying The The Tar tar pits).