Kmart uses a K as its logo.
Kelloggs
Flickr's logo has a blue k and red r in it.
l think its chocolate company
flickr
Kellogs
Calvin Klein
If you are playing the logo game, try: Konami
The k stand for Knight, one of the two Swiss who founded the company in a garage
The company that has a red circle logo with a white R in it is Rossignol
K-R is the logo of the company who made your ring.
knife (linoleum knife)