Delete Band Aid 30 and buy it again? Good luck, Sir Bob
There's one problem with Bob Geldof's plea to keep downloading Do They Know It's Christmas? over and over again.
It's very difficult to do.
Once you've spent your 99p on the charity single to help people suffering from Ebola in west Africa, you've spent it.
Even if you delete the track from your iTunes or Google Play library, you can't buy it again with the same account.
We can see where Bob is coming from, he wants the Band Aid 30 single to raise as much money as possible.
Speaking on Radio 1 at the weekend he said: "Even if you already have it, delete, download again."
Just to demonstrate how difficult that is, we'll give it a try.
Downloading the single is easy enough. Find it in the Google Play or iTunes store and in a couple of taps, it's yours.
The track will download to whichever device you're using at the time and present itself on your computer at home as well.
All good so far.
This bit seems pretty straightforward too.
Swipe left, or press the three little dots and tap delete.
Let's assume you're feeling generous and decide to spend another 99p and buy the song again.
Open Google Play or iTunes, find the track and repeat step one above.
But instead of a button to buy the single you're given the option to download it again without paying a penny.
Apple also allows iTunes users to send a track to a friend as a gift, so that's one option for people wanting to pay for it several times over.
Can it be done?
As far as we can tell, the only way to buy the single more than once would be using a different account each time.
In some cases, if a download did not complete, iTunes users may see a message warning them they are attempting to a buy a song they have already purchased.
Maybe use your friend's Google Play or iTunes ID? As long as they haven't bought the track already, that is.
It's probably easier to wait until the CD single goes on sale on 8 December and buy as many as you like for £3.99 each.
You can also donate to the Band Aid appeal by text message.
See all Newsbeat's other stories about Band Aid 30 on our special index.