There are more than eight hundred crypto currencies available in the crypto market, bitcoin is the first crypto currency in the market and this cannot be mined with computers or laptops as it requires more electrical and hash power generating machines, but still there are many other crypto currencies like monero, bytecoin, digitalnote, dashcoin and many other crypto currencies which can be mined at home using a desktop or laptop. The value of these crypto currencies will increase in the future. GPU or Graphic processing units can help to mine bitcoins and other crypto currencies.
Even mining monero with your laptop these days is not really worth it that much. Still, from your last point and the value of the cryptocurrencies increasing later in future, they are really worth a try, most especially if one has a free PC running and some free electricity.
I have heard of someone who mines monero with his official PC and leaves the PC running 247 since he does not have to pay for anything anyway. Hope he does not get to lose his job doing that anyway.