The most common in my family are:
mokajo = remote control
prinnles = Pringles (chips)
pritiful = pretty, beautiful
perkick = perfect
lallo = yellow
They all came from my brother, who had a tongue too big for his mouth, so had problems with certain phonemes. The best, however, is “chocolate bucket” which refers to the Czech Republic. My sister and I tried for about five minutes to figure out what he was saying that sounded like “chocolate bucket”. Finally he got frustrated enough to yell out “Where Mom lives!” The Czech Republic has been the “Chocolate Bucket” ever since, much to the confusion of various friends and relatives.
A more complete list can be found here.