Here's a recommendation: How to Mull Wine, or, How to Brew Pure Happiness in 3 Hours or Less | Serious Eats
I'll go cheap for mulled wine. Heated sake is usually the cheapest possible stuff as well, Futsu grade (normal, cheap, but drinkable). If you're drinking room temp (ish) or chilled, try a quality wine or quality sake. For heated/mulling wine, I usually go for something that's $3-6 per bottle. Usually Trader Joe's Charles Shaw wines, or some more expensive prespiced (though still decent quality) wine like Leelenau Cellar's Witches Brew. Very rarely, I'll go for something more expensive, but usually when I can't do something cheaper. For example, B.Nektar's Vanilla Cinnamon Mead which is good heated but is about 15 per bottle.
Secondary: GF Czech Lager
Waiting to be kegged, Italian Primitivo
Kegged&Ready: GF Orange&Coriander, GF Honey Lager, GF chocolate ale, GF English ale, Island mist (zinfandel), Island mist (cbry malbec).
Bottled: Infected Mead, Dry Hard ciders, Accidental Sorghumwine, various unnamed.