Boxing and unboxing: when does it come up?

Question

So I understand what boxing and unboxing is. When\'s it come up in real-world code, or in what examples is it an issue? I can\'t imagine doing something like this example:

Answer 1

It happens all the time when people do not know what the implications are, simply don't care or sometimes one cannot help but accept boxing as the lesser evel.

Strongly typed datarows will box/unbox pretty much all the time when you access a value-type property. Also, using a value type as an interface reference will box it as well. Or getting a delegate from an instance method of a value type. (The delegate's target is of type Object)