I was reading an MSNBC article about the Large Hadron Collider at CERN when I noticed that they claimed that CERN could currently accelerate particles to the speed of light.  I did not believe that was possible so I started composing an email to MSNBC rebuking them for misleading the public like that.  Before sending the email I decided to visit the CERN site and find what had mislead MSNBC.  Sure enough I found a page that claimed:

Using accelerators we can make single particles (like a proton) go as fast as the speed of light (300′000 km/sec).

So, I redirected my mail to CERN and made it much more polite and humble.  A few weeks later I got the following response:

Dear Mr. dos Santos,

thanks very much for your query. We are sorry for confusing you here. As a matter of facts, in this instance, we are approximating both the speed of light and the speed of the protons in the LHC to 300000 km/s. In reality, protons at the LHC move at 0.999999991 times the speed of light (at top energy - 7 TeV) and the speed of light is 299792.458 km/s.
I hope this clarifies your question. Thank you very much for pointing it out. Your comment is very useful because we are just in the preparation of a new web site.

Wow!  99.9999991% of the speed of light!  I knew they had reached high energies (7 TeV) but I had not realized how close to the speed of light that meant!