Go ahead, forget those annoying PINs. In the not-so-distant future, your local ATM is more likely to recognize you by your fingerprint or face than by a four-digit code. Not everyone, however, is ready for such a sci-fi world. In a new study by International Biometric Group in New York City, consumers tested three types of high-tech identification systems - finger scans, voice verification, and facial imagery - and rated their comfort levels with each one. Citibank, Chase Manhattan Bank, and Visa sponsored the study, no doubt because all three have strong interests in integrating these technologies into consumer products and services. They better keep the John Hancock option available: Some people still trust their signature over high technology.