#3. Hornswoggle
Hornswoggle returning to WWE would seem like an absurd and unnecessary one, but it would probably get the biggest pop at SummerSlam. It's quite obvious what Hornswoggle would return for - the 24/7 Championship.
R-Truth has time and again addressed Drake Maverick as Hornswoggle in the feud between Truth and Maverick for the 24/7 title, and it only makes sense for Hornswoggle to return and enter in the feud.
Maria Kanellis currently holds the title after winning it off her husband Mike Kanellis, but no Superstar has dared to pin Maria as she is currently pregnant. This could maybe change at SummerSlam, where we could see Hornswoggle return and pin Maria to win the title, and then a feud between Hornswoggle and R-Truth is set in motion.
The 24/7 title is one of the most exciting things on WWE television and the addition of Hornswoggle could just make things even funnier!