Yeast is microscopic, and so you'd have to have a "strainer" with .5 micron "holes".
Some brewers will filter their brew (many brewers do) under co2 to avoid oxidation with a .5 micron filter. Oxygen is the death of beer after fermentation, so it should never be poured through a strainer once finished!
Yes this is what I should have added. Straining and filtering are two totally different things. If you just want to clear some yeast out of your final product I would suggest "cold crashing". Chill your secondary (or primary if you skip secondary) 35 degrees or so for a few days before kegging. I do this and it seems to clear out a lot of the yeast very little sediment in the bottom of the keg. If your bottling I would do some research as I'm not sure how it would effect the yeast for carbing.