Just tracing some water features around what I guess must be the california aquaeduct. Wikipedia is quite a help in discovering the names of some things. Apparently we might have some government data source available for these, which would be better than tracing?

It's difficult for the renderers to do justice to a junction like this, where the right-hand lane of an elevated trunk road just disappears into the earth, emerging at ground level in a different direction.

In fact, this whole section of road is a nightmare to navigate around, where an incorrect lane choice can send you in unpredictable directions. The 'sliproads to exit and normal lanes to continue' convention doesn't apply...

I've traced some buildings on the University of Nottingham main campus from Yahoo imagery, filling-in names from memory (and with a few hints from the Wikipedia article)

http://en.wikipedia.org/wiki/University_of_Nottingham_Halls_of_Residence

It adds a new tag:

place=hall_of_residence

which may be worth rendering on campus maps.

In the meantime, I've lablled the residential buildings with the name of their hall (e.g. 10 buildings all with name=Lenton and Wortley, which shows-up on the map)

There are parks and woodlands marked inside the campus. The area tagging causes some problems:

To make a woodland appear above the generic "landuse=university" purple area, we have to use the layer attribute. But that makes some paths disappear 'under' the woodland. I don't want to put a higher layer on those paths just to make them render, since technically they're ground-level paths.

Multipolygon relations are being used for courtyards within buildings.

osm.wiki/index.php/Relations/Multipolygon