Intergalactic travel

The next step beyond interstellar travel. I've seen virtually nothing on this topic.

It could be done, I've considered, these ways, without using present-
day knowledge of physics:

1. Way stations. The space between the galaxies is not empty. Within
the local group, there may be about a billion stars out in inter-
galactic space.

2. A planet-sized ark, going on a *long* journey at some percentage
of the speed of light.

3. Stars get ejected from the centers of galaxies at *large* speeds,
up to 1000 km/s, by the supermassive black holes at the centers. Find
one traveling in the right direction, and the right kind, and hop into
an orbit around it.