Ok, I'll admit it. I use duct tape.
Seriously, I have a hand vac that I use. It has a "crevice" tool that flips up, so then the opening is about 1/2" by 1". Now, with duct tape, I attach a drinking straw to the end of the crevice tool. Just be sure to not completely seal the opening. Leave about 1/3 of it open so the suction isn't so high that it collapses the straw.
The drinking straw is small and flexible enough to fit into the tiny spaces around and under the bobbin case and feed dogs. I get it right down into the base of the machine and you'd be surprised how many wooly boogers come out of there. The best part is : because the hand vac has such a small dust cup, if I accidently suck up something I shouldn't ( oops ) I can find it without any trouble. This has been working well for me for years.