I was walking in Portland today and noticed a couple of button activated crosswalks that would give the crosswalk light about 5 seconds before the parallel-straight&turning traffic got the green light. Not enough time to cross 4 lanes of traffic+2 bike lanes+median, but enough to get a good start crossing.

I think the idea is to make pedestrians more visible to turning traffic, and not allow cars to try to sneak in front of them. Probably effective.

I'm trying to think if a similar control would help with right turns across bike lanes.
It might help for those bikes stopped at the light, but might be more dangerous for those cyclists that arrive at the intersection at full speed just as the light is changing.

Nonetheless, it seemed like an interesting concept.