Hi, alice,
Some opinions, added to those suggested by FD:
Discarding computer components endangers the ecology, since many of them are undisintegratable and can't be recycled, and need to undergo special treatment before discarding, but in undeveloped countries, they're just discarded in rubbish piles. In poorer districts in developing countries, people make their living by collecting this kind of electronic rubbish, and even burn them, causing toxic air all over the town.
