I've just received the strangest email:
I don't understand why anyone would send an email like this. It doesn't look to be asking for credentials of any kind. Is this a scam which is designed for you to engage with the sender?
It is possibly an attempt at Bayesian Poisoning of your spam filter. Spam filters work by analysing words in the email and assigning them a spam value. One form of Bayesian Poisoning is to send an innocuous email that contains mostly "good" words and one or two "bad" words. The spam filter will see the message as not spam and over time it can be trained to assign these "bad" words a lower spam value - which will allow more spam though.
See also How does Bayesian poisoning work?