There was a recent discussion on a listserv I monitor about what a florist might do who is suffering in the recession. One participant suggested "expanding their offerings beyond just flowers...some gifty/crafty stuff to compliment the flowers and get feet through the door and create incremental volume." Good idea, that.
One of my favorite resources is looking at the Economic Census for the Product Lines documents. The one for Retail Trade (NAICS 44-45) can be found here. For NAICS code 45311, found on page 173, you'll see that of the 22,750 florists in 2002:
3719 sell candy, 1209 sell other food stuff or 4061 selling some sort of grocery item (some sell both)
9268 sell some sort of kitchenware
603 sell jewelry
364 sell books
4810 sell games and toys
Again, these are 2002 numbers - the 2007 numbers don't exist yet - but it does provide some guidance for how an entity might diversify its line.
There are similar product line reports for:
NAICS 22: Utilities
NAICS 42: Wholesale Trade
NAICS 48-49: Transportation and Warehousing
NAICS 51: Information
NAICS 52: Finance and Insurance
NAICS 53: Real Estate, Rental and Leasing
NAICS 54: Professional, Scientific, and Technical Services
NAICS 55: Management of Companies and Enterprises
NAICS 56: Administrative and Support and Waste Management and Remediation Services Services
NAICS 61: Educational Services
NAICS 62: Health Care and Social Assistance
NAICS 71: Arts, Education and Recreation
NAICS 72: Accommodations and Food Services
NAICS 81: Other Services (except Public Administration)
This information is also available from Census' American Factfinder, but frankly I found it less than user-friendly.