Get one small bottle of Tropicana Smooth Orange juice (or whatever your favourite is).
Put in freezer. Ta-da! Juicicle!
On hot days, enjoy taking one around with you, and having a resealable bottle containing a lump of lovely cold ice and juicy goodness. Mmmm, delicious.
Then on a cooler day, suddenly fancy some orange juice, and spend half an hour gazing at a frosty bottle, willing it to get to the drinkable stage.