Please allow us to offer you the world's most authoritative definition of Technullities, a Lingovation originally coined by Douglas E. Castle after being forced to watch too many late-night television advertorials.
TECHNULLITIES are products or services thought up by great (albeit impractical) minds which either 1) serve no useful purpose; 2) are impossible to operate because of either inordinate complexity, poor ergonomic engineering, or are just not worth the effort in order to achieve the promised result; or 3) are never quite completed [usually well-funded, "big picture" projects which politicians and their private sector contracting affiliates truly want to impress either the world or at least their voting constituents with] which never are completed on time (if at all), and are always devouring money, taking them far beyond their originally estimated capital budgets.
Many a garage or spare room is filled to the brim with Technullities which were purchased through irresistible late-night sales pitches; by well-intended friends attending a bridal shower or a wedding celebration; and by lottery winners or recent estate beneficiaries who suddenly felt compelled to capriciously spend some of their newly-gained wealth.
While we cannot afford to build a Technullities Museum, we can offer you a few pictorial samples of notable Technullities which may held to make the term more memorable. Here is a fine place to start:
The NY Daily News Listing Of Stupid Inventions (50 of them)