I use a "footsie roller" for the bottoms of my feet. A wooden rolling-pin looking device, 8 inches long. Roll my feet over it. Gets rid of tiredness, cramps, for circulation.
Sold at college town health food and body lotion stores.
Do you take your shoes off ? I do.
Another DVT site:
http://www.bugbog.com/travel_health/...hrombosis.html