Taken from April '94 APIS:
 
FILENAME:  APRAPIS.94
            Florida Extension Beekeeping Newsletter
    Apis--Apicultural Information and Issues (ISSN 0889-3764)
                 Volume 12, Number 4, April 1994
...
     Bumblebees are big business overseas because of their
pollinating potential in greenhouse tomatoes, according to the
article ("The Busiest of Bees: Pollen Bees Outwork Honey Bees
as Crop Pollinators," in the February, 1994 issue of Agricultural
Research), and may soon be in the U.S.  This is corroborated by a
full-page advertisement in the January, 1994 issue of Fruit Grower.
An inquiry for dealers in "maintenance free bumblebees," suggests
there's money to be made by selling hives equipped with a special
feeding cartridge, transparent lid, and closeable entrance.  For
information, contact Biobest Biological Systems, Llse Velden 18, B-
2260 Westerlo, Belgium, ph +32/14/23 17 01, FAX +32/14/23 18 31.
....