To "put all your eggs in one basket" is to risk losing everything all at one time.
It is always a good idea to have more than one copy of your important documents, photos, music etc. Computers have problems, electrical problems, mechanical problems, user problems, and there is no telling when any or a combination of the three will strike.
OK, so you don’t want to buy an external drive. I can understand that. Money can be tight for all of us, but there is a way to spread the load if you happen to have a home network sporting multiple computers. It isn’t an ideal situation but it is better than the scenario shown in the graphic..
Assuming that your computers are all connected to mains power via surge protectors, it is unlikely that you will have multiple failures at the same time. I am also assuming that all computer users on the network are trustworthy.
So, all you have to do is go to Network in your Windows 7 start menu, click on Network, and then locate the PUBLIC folder in the user account on the recipient computer. The public folder is NOT a secure place for long term storage but it gets over permissions problems for the purpose.
You then copy whatever you want from your computer to the OPEN public folder. Once copied across, you now create a folder and then move the data out of the public folder into your newly created storage folder.. It will take time, but the reward is obvious (look at the graphic) and it will not have cost you anything other than time.
And now for the ‘tip of the day’.
Do NOT transfer files across a wireless connection if there is a large amount of data to transfer. It takes forever. Connect both computers to your router via RJ45 Ethernet cable. You will more than double the speed of the transfer. To ensure that the Ethernet cable is used, temporarily disable your wireless adapter..