Over at Not Quite Vintage, Colleen mentions that she can't concentrate when real people are talking, but can when the TV is on. (Along with cute quilt block patterns.)
When I was writing my thesis, I needed "company," as I was holed up for weeks, but real people were too distracting. I would put the TV on (no cable, but in Boston, so two PBS stations) nonstop. When it got too interesting / my deadline got closer, I switched to only the more boring PBS documentaries (steamboats, anyone?). Then finally to a rotating constant run of High Society and The Philadelphia Story, over and over (it was a year before I could watch them again!), as that provided me with "company" but didn't draw my attention in the least. Only in the last two days was everything turned off (and my dear roommates plied me with bananas and buttered toast).
What distracts you?