#2 suggests you may be underpaid. I'd go to your boss privately and tell him you've thinking about leaving to do a startup because you don't feel challenged at

#2 suggests you may be underpaid. I'd go to your boss privately and tell him you've thinking about leaving to do a startup because you don't feel challenged at work, and this is hurting your productivity and interest in the job. All of this is true, you're just afraid to say it because of an innate desire for conflict avoidance. Be honest with the people around you about what you want (part of this means thinking it through yourself...). In a worst case scenario you lose your job. But if you're really ambivalent about leaving, giving notice like this should alleviate any guilt over quitting and being honest should keep you on better terms with people than the alternative. And you never know. Perhaps your boss will give you a raise or otherwise help solve your motivation problems.