What does £36.21 look like?

It looks like this:

Or maybe this:

 Or even this:

Because when you want this stroller:

 Mothercare will charge you £35, but the canopy and essential rain cover are an additional £20. So you check the British equivalent of kijiji to find if cheaper. And you do - someone is selling it for only £15!! Only they live in a neighbourhood called Cherry Hinton, which is either an hour & a quarter on a bus, or 35 minutes on a bike. So, you get on your bike with an empty backpack, get your cones over to Cherry Hinton, and strap that bad boy of a stroller in the bag and on your back. Oh, and on the way home you get a little bit lost, and start thinking, "I'm sure I didn't go past an uncontrolled railway intersection..." or "Hmmm, I would probably remember passing an airport, wouldn't I?". Luckily, you have your map, and as you're quickly checking where you are at the next crossing, you realize you're really quite far away from where you should be. In fact, you've ridden around half the perimeter of Cambridge airport.

While you're looking at the map, realizing that the streetlights are all coming on, and starting to feel a little bit bashful, a helpful driver stops and asks you through the window if you're alright. You respond that you're fine, and just taking a different route home (i.e. you lie). He looks at you and says, "You have a pushchair. On your back." and you respond, "Yes. I know." and he drives on. You do a u-turn and get on the right road this time.

And that's when you decide: it's time for beer. Alas, you know there's none at your house. So you stop at the store by your house, and as you're locking your bike up (which is a real challenge with 2 feet of stroller behind your head), you overhear two teenagers who are looking for a bootleg talking about you, saying, "Nah, she's got a pushchair in a backpack. She's not a good choice." Ha! So you get your beers, and get yourself home, the whole while congratulating yourself on (a) getting the stroller at least halfway in the backpack, (b) not falling off or getting hit by a car, and (c) sacrificing £3.79 of the "saved money" for two celebratory Budvar beers.