Let's suppose one day you stand up in the EU parliament and shout "Alright, don't worry folks, I will rescue the Euro!" and you go to your bank to withdraw the 750.000.000.000 € for the ESM...
As it is a rather large sum I guess the cashier would give it to you in handy 500 € notes (the most valuable bank note there is on this planet). You would end up with 1.500.000.000 Euro notes. If nobody is there to help you, you would have a very big problem now. To be more precise, you would end up with a stack of 500 € notes that weighs 1680 tons and has a hight of 225 kilometers.
Well, this is not exactly right. You need to consider that the bank notes in 225 kilometers hight are practically weightless, since they are in outer space. To calculate the actual weight of such a tower exceeds my mathematical skills. So let's assume you don't pile them up in one stack but form a cube with them. You would end up with a cube measuring roughly 14,5 m on each side (ever jumped from the 10m spring board?). To move the money you would need about 68 trucks, considering the maximum truck payload of 25 tons in the EU.
Alright. But what if the bank is closed and you need to get the 750.000.000.000 € from a cash machine? Probably you would end up with a lot of 50 € notes. With 15.000.000.000 50 € notes to be more precise. If you thought you had a problem with the 500 € notes, then you are in a real mess now. Now you would be faced with 13800 tons of 50€ notes that form a stack 2250 km high. The International Space Station ISS is 380 km above earth. So you could build almost six stacks of 50 € notes reaching the ISS. Or you could build a cube that is 29m long on each side. To move the money you would need 552 trucks.
But why should you rescue the Euro? You might just as well do something else with all that money. But what?
You might buy the most expensive car. The Bugatti Veyron Super Sport sells at 1.850.000 €. So you could buy 405.405 Bugatti Veyrons. But what the heck should you do with so many Veyrons? You should buy something more expensive. An Airbus A380 costs 150.000.000 € a piece. That would enable you to buy 5.000 Airbus A380, enough to host 2.625.000 people. Still not expensive enough!? So how about a yacht then? The 163 meters Abramowitsch Yacht cost supposedly 400.000.000 €. So you could buy 1875 of those. If you sink one a day, you could sail the seas for more than 5 years in utter luxury. Well, still doesn't make sense!? It is kind of frustrating being faced with spending so much money. How about simply giving the money away then?
You might give your money to the EU citizens. The EU which consists of 27 countries by now, has 500.000.000 inhabitants. That would make 1.500 € each, not too bad! Or you spend it in Africa which has 1.000.000.000 inhabitants, that would still make 750€ each! Even if you give money to everyone on this planet it still makes for 107 €. It is not very much, but I guess it would still be highly appreciated.
Well, I hope this helped you to get a better feel for these large numbers.