Today I learned that (perhaps obviously in retrospect) the wifi signal strength meter on your laptop/phone/tablet indicates how strong it is receiving the signal from the access point.  There is no guarantee that the signal in the reverse direction is being received so well, or at all.

If you boost the "transmit power" setting on the router (as you can with some firmware, including dd-wrt and friends), it will make your signal strength meter go up, all right, but you might actually get worse results.  In particular, you could get that suspicious behaviour I'm sure we've all seen, where you have lots of bars but still can't get an IP address.  Hmmm...

Also, from my desk, I can hear 15 guest access points, and 17 corporate ones.  (Presumably some of these overlap with each other.)  That's a lot.  But another thing I learned today is that too many access points being visible from a particular spot can actually make things worse because they interfere with each other.  I'm sure whoever laid out the office wifi network does a fancypants job, but I wish I knew what tools they use and what their algorithm is.  I guess probably I could track someone down and find out.