The Flash is a superhero that was created in 1940 by Harry Lampert and is owned by DC comics.  The logo is very popular and recognizable among those who love comics or superheros. The logo shown here look like a a vector image of the original.  The bright colors used in the logo help with recognition.  I don't think the logo has changed since it was created in 1940 so this would also help with recognition as it has stayed consistent throughout the years. The colors are meant to represent bravery, speed, and optimism.

Info from -    http://famouslogos.net/flash-logo/

The Ravens logo is well known especially for anyone who lives in and around Baltimore.  The team itself was named after Edgar Allen Poe's poem "The Raven".  Not a lot of football teams have purple in their logo so the Raven's logo tends to be very memorable.  The logo that is currently being used was introduced in 1998 and has been in use ever since. The logo is both sharp in design and color which helps it to stand out.  A custom typeface was used for the logo and it matches the bird very well.

Info from - http://famouslogos.net/baltimore-ravens-logo/

The Federal Express logo is very recognizable, at least in its current form.  I like the newer logo much more than the old and it seems everyone else does too, as the current logo has won some design awards.  The old logo was designed by Richard Runyon in 1973, and while there is movement in the design it lacks the appeal that the new one has. In 1994, Lindon Leader of Landor Associates designed the logo that is in use today. The colors for the "express" logo are blue and orange while the colors for FedEx ground are blue and green.  The colors for "corporation" are shown above.  It is nice that the colors remain consistent but still vary slightly depending on the department in the company. The arrow that is positioned between the Ex is a very good representation of the company, and it is great because once you know it is there you can't forget it.