I kegged an IPA on 2/10/13 and I washed the yeast. I ended up with 6 pint-sized mason jars of washed yeast in the fridge. I had been making starters out of them and it was working fine. Yesterday, I had a wild hair and decided to brew at the last minute. As I was mashing the grain, it suddenly occurred to me that I hadn't made a starter. All I had was one last remaining pint jar of yeast in the back of the fridge that was almost a month old.
Well it was obviously too late to back out of brewing so I took the yeast out and set it on the counter to get to room temp. Worst case, it wouldn't take off and I would have to re-pitch.
After I brewed and racked the wort into the primary, I shook the jar up really good and poured the whole thing in, trub and all. I figured that I would need all the active yeast out of the jar that I could get.
That was yesterday at around 3:00. There was still no airlock activity by the time I went to bed but that didn't bother me much. I got up this morning and it was bubbling away.
So no more yeast starters! All I need to ferment a 5 gallon batch is a pint-sized jar of washed yeast which is good for at least a month after it's been washed.