At the table in Kringle Feast, one of the green legs belongs to Lifty and the other to Shifty.
Although they are identical twins, Lifty's voice is slightly higher pitched than Shifty's voice. This has led some to believe that he is the younger of the two. However it was recently confirmed by Kenn Navarro on Twitter that they were both born at the same time.
Every episode that Shifty survives in has an extremely large cast of characters.
Shifty's MySpace Profile claims in Shifty's marital status that he is currently in a relationship. The page also states that he and Lifty are both 28 years old, though this is probably just a throwaway gag.
Despite being kleptomaniacs, Lifty and Shifty had reasons to steal in Wheelin' and Dealin' (They needed wheels to start the race and a wheel to avoid crashing into an ambulance), Meat Me for Lunch (The food in their fridge ran out leaving them with nothing to eat), Swelter Skelter (The heat was too intense and they needed to cool down), and Buns of Steal (They were starving).
He and Lifty are voiced by Kenn Navarro, the same voice actor who does Cuddles and Good Flippy, although Lifty and Shifty sound nothing like Cuddles and Good Flippy.
Lifty and Shifty say "Uh-oh!" when something goes wrong.
Although they are identical twins, Shifty's voice is slightly lower pitched than Lifty's voice. This has led some to believe that he is the older of the two. However, Kenn Navarro has confirmed that they were born at the exact same time.
Lifty and Shifty are the only characters to have the same amount of starring, featuring and appearing roles for now.
In the episode Class Act, Shifty can be seen dragging Lifty, so it is evident that even though Shifty has killed Lifty before (like in Milkin' It) and left him to die (like in Sea What I Found), he still tried to save his brother. However, at the time there was no danger to Shifty, so it is fair to assume he cares for his brother, but at any sign of danger, he will leave him behind.
His and Lifty's laugh is unique to them. Most other HTFs either giggle or laugh.
This could further support the theory that they steal out of necessity instead of greed.
According to the "Collect Them All" section, Shifty has a gambling problem.
In early episodes, his and Lifty's pupils are normal like any other Tree Friend (like Pac-man pupils). However, occasionally in early episodes, and always in later episodes, their pupils dilate/shrink, making them appear more mischievous.
The two were possibly made green to match the color of dollar bills.
The two were made possibly green to match the color of money.
Lifty & Shifty are the only characters who have triangle-shaped ears.
In the TV series, the only episodes that Lifty and Shifty do not appear in are "Seventh Heaven", "Behind the Eighth Ball", and "Ten Speed".
Even though Lifty and Shifty are always seen together Shifty has a higher kill count (a total of three kills more than Lifty).
There has only been one episode (Cheesy Does It) in which one of the raccoon twins dies while the other survives. They usually either die or survive together (although sometimes they suffer different deaths).
Shifty is the first character to kill another character while he was already dead.
He and Lifty do not always die the same deaths, and they do not always die at the same time. Junk in the Trunk and Buns of Steal featured the some instances where they did not die at the same time or one right after the other, while Cheesy Does It marks the only episode where one survives but the other gets killed (in this case Shifty gets killed while Lifty is left unharmed).
Shifty's most frequent victim is his twin brother Lifty.
Because of a goof in the opening credits of As You Wish, Lifty and Shifty are two of the three characters to have only have their names and not "starring" or "and" in the first season of the TV series, the other being The Mole.