How small? I bought a N100 system from Protectli which I’m happy with. It should work better than a pi according to the specs - but I never tried a pi so I can’t say if it really is. However this is bigger than a pi. I have an old system76 Meerkat, which is much smaller (I think this is the NUC form factor?), but my system is 8 years old and so not really comparable to anything modern, but that is an option.
You should know that wd is for water displacement. If you are trying to do anything else there is a better chemical you should use instead.