Sometimes I have some hours or days to kill, meaning I have time for a quick freelance job. The problem with most sites on the web is that they require a comparatively lengthy application process for each project. This means that by the time my application is accepted, my free period has already ended. Also many projects are way too big, requiring more than just some hours or days. (In fact many projects are unrealistically bloated, and I wonder if they ever get finished.)

Are there any sites that allow me to find quick jobs, and ideally ones that require high skill, resulting in good pay?