Personally I like buttons w/ a magnifying glass icon. The problem I have is with search fields that have no button and assume users know to hit <enter>. Respond

Personally I like buttons w/ a magnifying glass icon. The problem I have is with search fields that have no button and assume users know to hit <enter>. Responding to the return keypress is a good usability practice, but there should also be a button to click. A good example is stackoverflow.com. I've entered a search term and, by reflex, clicked the Ask Question button because it's in the vicinity.