Hello all;
My bees and I live in Bequia, a small island in the West Indies.  So far, we are considered to be mite free; however, I am sure they will get here sooner or later. I would like to start a counterattack before I end up with an out-of-control situation.  Reading posts and searching the BEE-L archives have led me to evolve the following strategy..  
1) Screened bottom boards - simple, cost effective, environmentally friendly.  The merits of these boards are well known to List readers.
2) Food Grade Mineral Oil. http://www.beekeeping.com/articles/mineral_oil.htm is a good discussion by Dr. Pedro P. Rodriguez.  His theories and experiments are sensible and workable.  He advocates, among other things, a thin bead of FGMO on the top bars.  I am altering the good Doctors strategy just a bit.  I reason that if I can keep the mites away from the ladies in the first place I won't have to deal with a hive full of them later.  I will smear a very light film of FGMO on my landing boards.  This will be easy to clean, easy to re-apply, easy to monitor, is enviromentally friendly and will do the same job, I hope.
3) Essential Oils. http://www.wvu.edu/~agexten/varroa2htm#Essential is a good discussion of essential oils to combat the dreaded mite.  Near the end of this discussion there is a section titled, Comments on Natural Resistance to Varroatosis.  The first paragraph of this section refers to some bees being naturally resistant to mites.  The authors speculate that it is due to the bees foraging amongst plants that produce the essential oils which have been proven to control mite populations.  So, I will plant lots of mint, which is useful for we humans as well, and hope for the best.
These steps might not be practical for commercial operations.  If these are practical ideas, and I don't see and glaring flaws here, then it might be prudent for hobby beekeepers like myself to adopt a similar strategy.  Anything we can do to retard the build-up of mites tolerance to Apistan, or whatever, has to benefit us all.
I would welcome any comments or criticism of my strategy.
Bob in Bequia