I don't get into astronomy much any more, but I thought this Ars Technica article was pretty interesting. The article talks about a paper to be published in the journal General Relativity and Gravitation. The paper claims that in 100 billion years the universe's cosmological evidence will have disappeared. The cosmic microwave background will be buried in interstellar plasma, and light from other galaxies will have been redshifted (from Hubble expansion) too much to be detectable.
Reminds me of that Simpsons episode: "Let's burn down the observatory so that this can never happen again!" (If I only had a dime for every time I've thought those very words.)