Cold Cathodes are simply tubes that light up because of the gas inside. They are similar to Neon, but as the name implies, they run cold, so no worry about excess heat. They serve no purpose other then decoration and to make a case with a window look good.
Baybuses are fan controllers. They sit in a 5.25" drive bay and have knobs that you wire to your fans so you can control their speed and noise.
Both can be bought at Newegg.
<a href="http://www.newegg.com/Product/Product.asp?Item=N82E16813999503"target="_blank">Vantec Fan Controller</a>
<a href="http://www.newegg.com/Product/Product.asp?Item=N82E16800888026"target="_blank">Cathode</a>
:)