In Japan, instead of signing a document, you use a "hanko". This is your personal name seal.
Signatures are accepted occasionally, but large purchases, such as a car, often require a signature. hannko has two types. One is a casual seal, called a "miri-in," which can be used for bank, business, and city hall documents. The other is a formal seal called a jitsuin, which is registered at city hall.
You can make their stamps in katakana!