You can try to use ledger nano or what people who do not really wanna commit to buying something that is worth $90 just to store cryptos, you can try using a thumbdrive wallet but this is only for MEW or other wallets that requires files to login to the wallet. You can use MEW for ETH or Altcoins and the JPSONE file can be kept in ur thumbdrive for save keeping and plugged in only when you want to