IBM Thinkpad T61

Hardware Overview

acpi_ibm seems to work just fine. No issues noted.
volume control buttons control the application with focus; not the global sound mixer
drm2 supports the graphics hardware with hardware OpenGL
middle mouse button seems to not work out of the box
suspend/resume works.
Do not disable "Security -> IO Port Access -> Modem" in BIOS , otherwise it will fail to resume.
Having tpm.ko loaded breaks suspend. TPM doesn't work after resume.
USB power after suspend/resume cycle has been fixed in FreeBSD-11.