Programmers need all the help they can get. It can be a thankless task sometimes and language designers with the best intentions cause misleading behavior to occur even in the simplest of code. The authors of Java Puzzlers, have mined the Java specifications misleading problems that cause issues in production code. It makes interesting reading, it can also points to scary traps that could trip up the hapless programmer. They do however recommend a tool called findbugs that will literally find bugs in your software.
Last year I started to learn Chinese. But didn't get very far. I've found out that the eclipse-platform has been used to create a program to help with learning Chinese script. It is called Zhongwen Development Tool or ZDT. (Zhongwen is Chinese for Chinese). The program helps when learning Chinese characters and tests your chinese character and radical knowledge using a flashcard system.
I noticed recently that Warren Smith has an interesting page on skiing. He talks about how biomechanics and psychology are not always taken into account by ski teachers and can contribute to skiers remaining at an intermediate level for longer. He lists some typical but not exhaustive issues that can be solved with more awareness: giving tips on diagnosis and remedies.