I remember Enercell for batteries, Supertape for cassette tapes, Genexa TVs and VCRs, Archer TV/radio aerials and distribution systems, Micronta meters, and, of course, the Science Fair 200-in-1 electronic project kits.

The branch opposite my school had several "characters" amongst the staff who would amuse themselves by pelting you with dud resistors if you refused their entreaties to sign up to the Battery Club. A great place for nerdy teenagers to visit, but I can't imagine them actually ever having sold very much...