I once saw reference to a noun that identified a person whose physical presence disrupts equipment, particularly electronic devices. Any ideas?
So long as you're looking for more of a humorous term than a scientific term, I might suggest gremlin.
"Electric human" appears to be one label for the person you describe. See the following website: http://amasci.com/weird/unusual/zap.html, where there are numerous links to various websites, some highly suspect and purely anecdotal in nature, and some with the cache of respectability.
The Princeton Engineering Anomalies Research (PEAR) at http://icrl.org/ is one of the respectable links. The P.E.A.R. group at Princeton University researched the non-electrical effects which minds could have on electronic devices. The PEAR website provides a link to a newer Princeton-related study group called the ICRL (International Consciousness Research Laboratories). From the ICRL website:
"ICRL is an international, interdisciplinary, and intergenerational consortium of some 75 members, most of whom have been associated with the Princeton Engineering Anomalies Research (PEAR) laboratory at Princeton University as interns or research collaborators over its thirty-year history."
As an adjective staticky in the sense of "2. Relating to or producing electrostatic charges." This would do for someone who touches the keyboard and the computer crashes before they even type, for example.
It often is literally static electricity causing such glitches, though I couldn't see this applying to non-contact disruption.
I would suggest disrupter:
To interrupt or impede the progress, movement, or procedure of http://www.thefreedictionary.com/disrupter
In this case, the subject is interrupting the electronic devices.
A jinx can out-murphy just about anyone, any time, any place, any where, no how!
Recent since the ?late 1990s? is: SLI-der.
After SLI Street Light Interference phenomenon, people who claim that, while walking at night, the gas-discharge streetlights turn off one after another as they approach.
Contentious is the first word that comes to my mind.
M-W definition: likely to cause people to argue or disagree