First up: Only kidding on the keeping front!
A beautiful cat followed me home last night after I stroked it - I went into the house and thought no more of it. It made its way into our back garden and when DH opened the door to put the bins out it came inside and had to be shooed out again. It was still hanging around the (closed) back door this morning as if it thinks it lives here, and has come in and had a wander around when I opened the door.
I'm familiar with the cat-stealing neighbour threads, so I haven't fed it, shut the door behind it when it's wandered in, etc. - hoping to appeal to collective MN wisdom on what to do if it keeps hanging around. It has no collar (flea or name) but looks in far too good condition not to belong to someone. Is there a chance it doesn't know how to get back out of our garden having made its way in? How long would you leave it before you took it to the vet to scan for a microchip? I hate the idea of someone else being stressed out about their lost pet...
Apologies if these are common sense questions - we aren't cat people as DH is a little allergic, so don't really know 'normal' behaviour (although I'm tempted to let this particular cat rub all over the soft furnishings to see if he can really tell 
- did I mention it's gorgeous?)