To add on, another promising technique is ultrafast electron diffraction (UED). You can get atomic space and time resolution (sub-angstrom and 100 fs) already.

To add on, another promising technique is ultrafast electron diffraction (UED). You can get atomic space and time resolution (sub-angstrom and 100 fs) already. It's just a matter of scaling up beam quality to the point we can study complex macromolecules. UED will also fit in a single room while the worlds only XFEL is miles long. (I work on instrumentation improvements for XFELs and UED.)