A new cheat that will be included in University will allow you to place objects diagonally. This is revealed by MaxoidTom, a Maxis employee, in this post at the ModTheSims2 forums. He won't reveal the cheat yet, but Snooty from SnootySims does reveal that boolprop mayPlaceDiagonally [true/false] might be the cheat in question. It's unsure if this is the actual cheat, but it does exist in the original Sims 2 files but is disabled. It might be enabled in University. This is said in a post at the SimParool forums (post and most of the site in Dutch). It's unsure if this is the actual cheat or not, but Maxis will probably reveal that later.