I just cracked open a Buss Fuses ceramic fuse. The fuse is a sand-filled ceramic tube. I'm using these ceramic fuses on my Maggies 3.6R. The fuses are mounted on the speaker frame, so they are susceptible to vibration from the drivers. There is one fuse for the mid-range driver and one for the ribbon tweeter.
For the ones who joined the discussion in the last few days, I recently compared four fuses, two glass and two ceramic, including the HiFi-Tunning fuse. The sound was a lot cleaner with the ceramic fuses than it was with the glass fuses. Of the two ceramic fuses I tried, the Buss ceramic fuse provides a cleaner, more balanced sound. There is more energy and definition on the upper-base, lower mid-range region. The highs also have more clarity and definition. The HiFi-Tuning fuses were almost as good as the Buss fuses, but the latter has a much cleaner presentation.
It seems to me that the sand-filled ceramic tube absorbs vibrations quite well, hence contributing to the cleaner sound. Also, the filament gets thicker in the middle http://cgim.audiogon.com/i/vs/i/f/1220802079.jpg
I purchased the Buss ceramic fuses from: http://www.mcmaster.com/
The fuses are under the "Lighting and Electrical" section and cost $6.06 for a pack of 5. They are UL listed.