This morning I received the following email:

Myself, my wife and my son are visiting the UK for 15 days and we are jus shopping / sightseeing. This is why we will need a translator service of someone we can go out with from March 18th to 2nd of April and will be willing to spend six hours everyday with us during our outings either from 9.00am – 3.00pm or 12.00pm – 6.00pm depending on when we choose to go out. Please let me know if you are interested in offering this service and we can proceed asap as I will like to make payment before our arrival.
Thanks.
Sadiq.

This is a scam that has been going around recently, targeting interpreters. I know about it because I sometimes have a look at the forums at Proz, an online community for translators, and it has been mentioned a few times, here and here, for example.
It goes like this: you agree on a price and Sadiq sends you a cheque for X, which does appear in your bank account. Soon afterwards, he changes his mind on the amount, or claims he made a mistake and transferred too much on your account, and asks you to send a cheque covering the surplus amount. He’s hoping that by the time your bank realises his cheque is fake, he’ll have had time to cash yours.
If you want to fight back, check out 419 Eater, a site about scambaiting, which is "a dialogue with scammers, simply to waste their precious time and resources. Whilst you are doing this, you will be helping to keep the scammers away from real potential victims." Some of the exchanges with scammers are hilarious. If I wasn’t quite so busy with work (and slightly scared of dealing with criminals), I might well have indulged in a little correspondence with Sadiq…