Thanks, guys. I'm going to get some mace tomorrow. I had a harrowing commute this morning - a near miss in Sellwood, followed by the usual thrill ride that is the Sellwood bridge. :-0
The possible spookiness of the Springwater trail looks pretty inviting at this point (hypothetical attackers vs. the feeling my days are numbered if I continue to play on the bridge), and I rode across the Hawthorne bridge for the first time this afternoon and could not believe how peaceful it felt. I also had no problem parking my bike at school - PSU has incredible numbers of bike racks.