Giving notice is a courtesy. I think it's the 'right' thing when you think you and your employer have mutual respect for each other. However, if you feel you

Giving notice is a courtesy. I think it's the 'right' thing when you think you and your employer have mutual respect for each other. However, if you feel you are being underpaid, under-appreciated, or asked to do unethical things, why do you owe them anything? Just get out! Maybe if it stings a bit, they'll treat their remaining/future employees a bit better (or go out of business).