In the Hawaii level, there is a gold tiki statue against a wall. Jumping into this statue sends you into a tunnel which ends in a red room with a small volcano/tiki and the message "Evil Tiki" before returning you back to the beginning of the level.
In the pre-set skaters in Create-A-Skater Mode is a female skater named "Sheena" dressed in a punk rock outfit. This may be a reference to The Ramones song, "Sheena is A Punk Rocker".
In the "Moscow" level, if you manage to bump the head off the snowman with your skateboard, blood will begin to spill out from the snowman's neck and the text "Fatality" will appear. This is a reference to the Fatalities in the Mortal Kombat series.