An interesting post this morning from Merlin Mann on his 43 Folders blog about recent research on multitasking. This includes yesterday's New York Times article which cites several studies including one looking at Microsoft workers and the effects of interrupts on their work:

a group of Microsoft workers took, on average, 15 minutes to return to serious mental tasks, like writing reports or computer code, after responding to incoming e-mail or instant messages. They strayed off to reply to other messages or browse news, sports or entertainment Web sites.

The effects on the individual are measurable in terms of cognitive performance the NYT article also cites a startling figure for the overall cost of multitasking.

The productivity lost by overtaxed multitaskers cannot be measured precisely, but it is probably a lot. Jonathan B. Spira, chief analyst at Basex, a business-research firm, estimates the cost of interruptions to the American economy at nearly $650 billion a year.

So far none of the studies have directly discussed the impact of IM's during Torts...