BTX seemed like a logical solution to the dilemma of ever-increasing heat inside modern high performance PCs. BTX ("balanced technology extended") is to re-lay out motherboard components and re-architect internal airflow to maximize cooling while minimizing noise. But you need a BTX chassis and BTX-compliant cooling solution, which consists of a heat sink and cooling fan. The cooler we tested in late 2004 weighed 2.75 pounds (or 1.25 kilograms) and was massive.Other failed tech trends are: HD video on the PC, HD digital audio, Windows XP 64-bit, HD optical drives, copy protection for music CDs, iPod competitors, the digital home, Google's Gmail and dual graphics cards. Read on over at ExtremeTech.
Top ten failed technology trends for 2005

Here's a look at the top ten failed tech trends for the past year, the article kicks off with the BTX form factor: