How To Clean A Thermos?

I made a big deal last year of how I went for months without having any coffee. It was quite an accomplishment, ifidosaysomyself(andido). Another huge (related) accomplishment - not having washed out my coffee Thermos for months. When I climbed back on the brown bitter wagon (poetic!), I - perhaps not surprisingly - found a disgusting hardened coffee residue agar sitting at the bottom of the Thermos, woefully out of reach of my dishrag.

I tried to scrape the sludge from the bottom with a butter knife. I tried filling the Thermos with hot soapy water and shaking it like I was making a margarita, angrily. I tried soaking it overnight. I tried to shame it clean by staring at it long and hard in a disapproving fashion. All attempts were unsuccessful, but I continued to use the Thermos regardless, figuring that if I couldn't manually remove that crap through all of my above efforts - it was now part of the Thermos itself and not likely to dislodge into my delicious coffee.

Until this morning, my optimistic figuring had not been visibly proven wrong. This morning, to quote one Wayne Campbell, I nearly chundered when I saw hundreds of horrible bacteria-ridden black/brown flakes as I emptied the last third of the Thermos into my mug (having already consumed the previous two-thirds). Their grotesque floating faces laughed at me, and told me I was going to die of my own cheapness and laziness.

They may be right.