Whether it's a stray umbrella left on the bus, or a wallet dropped in the street, we've all unwittingly added to the great piles of lost property sitting in dusty corners around the UK. In a typical year the London Underground alone finds 250,000 pieces of lost property - and estimates suggest that around the country more than a million items go missing.
In among these enormous piles of lost property are some real oddities. We reveal ten of the weirdest.
> 1. Transport for London keeps a vault of lost items - most of which are kept for three months and then either sold on or thrown away. However, they will go to extraordinary lengths to return some items.
There was the 80-year-old who had his suitcase stolen at Heathrow - containing the ashes of his brother who had died in Germany. The thieves raided the bag on the underground, and left the urn. The lost property team read the name of the crematorium on the urn, and wrote to them in order to find the owner of the ashes. They were eventually returned.
2. Another item was reclaimed fairy quickly: breast implants which had been left on a tube by a courier on his way to Harley Street.
3. Some items are not claimed and yet not thrown away - as they have enough curiosity value to keep. One of the long-term occupants of the vault is a stuffed puffer fish.
4. In some instances you have to wonder whether the item in question was taken onto public transport as a joke. This can surely be the only reason why the lost property department is home to a grandfather clock found on the underground.
5. This may also be the reason why a theatrical coffin was left on a tube and ended up in the lost property department.
6. Lost items at the airport can be much more valuable than those left elsewhere. London City airport recently published a list of its most unusual finds. At the top was £50,000 in cash - followed by a bag of diamonds.
7. A survey by Travelodge revealed that in Newcastle, an extremely rare 1780s Toby jug, worth £3,000, was discovered under a pillow. It turned out that the guest had bought it at an antique's fair, hidden it under the pillow for safe-keeping, and forgotten to take it with them.
8. The same survey revealed that a room in Nuneaton was found transformed in to a Christmas wonderland with lights, decorations, and the remains of a Christmas dinner.
9. In 2009 a bag was handed into Waverley Train station's lost property department in Edinburgh: it contained a dead octopus.
10. Europcars at Blackpool Station found a life-size dummy, dressed as an old lady and left in the boot of a Ford Focus. The employee who opened the boot to check it had the fright of his life.