BOINC itself is the white-label open-source[1] tech that other projects use, including SETI@home. I participate in IBM's World Community Grid[2] project, which uses the BOINC client. (it's running on my home machines, including some old/spare Android devices)

The IBM project is definitely active — their homepage currently says there are 721k volunteers participating, and there's a monthly email newsletter that covers their sub-projects' progress.

For an example of a current project, see OpenZika[3].

I see projects like BOINC and Jason Scott's ArchiveTeam Warrior[4] as a sort of "botnet for good" — if you have some bandwidth + margin in your monthly electricity budget, why not? I'm essentially spending a bit of electricity each month to help contribute to (and be a participant in) these projects. Their marketing must be working, because it "feels good" to be a part of them. :)

I don't know enough about CPU use + electrical costs to truly gauge the impact of my devices, e.g. vs. spending the same amount of $ on a fast, modern server running on clean power in an Icelandic datacenter. But having an old laptop or two + a few old Android devices running 24x7 hasn't noticeably appeared on my monthly PG&E bill.

[1] https://github.com/BOINC/boinc

[2] https://www.worldcommunitygrid.org/discover.action

[3] https://www.worldcommunitygrid.org/research/zika/overview.do

[4] http://www.archiveteam.org/index.php?title=ArchiveTeam_Warri...