UGrokIt (ugrokit.com) just started shipping such a thing. (Disclosure: I have worked with UGrokIt.)
There's a difference between static and dynamic content. Aliasing artifacts that are perfectly acceptable at 300DPI on a non-moving line can be pretty annoying on a moving line. The same goes for other high-frequency features in images.
The behavior of floating-point arithmetic. This wasn't covered in my university curriculum, and was necessary in tasks including graphics, machine learning, and finance once I got into the industrial world.
As a manager, possibly the single most important skill for me was learning the ways to estimate the time required for complex programming tasks. Once you're tackling problems beyond the scope of a single programmer, coordination is required, and schedule estimation is essential.
In the US, the Environmental Protection Agency has stated that concentrations of up to 100% are safe for adults. The American Academy of Pediatrics has stated that concentrations of up to 30% are safe for children. In both cases the repellent must be applied properly! Consumer Reports recommends 30% to 50% for adults, and helpfully explains that higher concentrations last longer, but don't repel any more effectively than lower concentrations.
Personally, I've used 100% DEET for a week at a time, a few times a year, over several years, without any of the documented side-effects. If someone is in one of the (relatively uncommon) situations where it's appropriate, I wouldn't hesitate to recommend trying it. Otherwise, adults can use 30% to 50% DEET and reapply as needed. My kids use 10% to 30% when necessary.
All this is subject to the usual cost/benefit tradeoffs, of course. There appears to be a lot of data showing that the risk of using DEET is low, so if West Nile or some other mosquito-borne disease is threatening, the benefit probably outweighs the risk.
Try reading Vitals by Greg Bear.