I also discuss with fictional characters. Showing them my home town and debating the merits of the present vs. their timeframe (I never read or watch anything set in the present) are favourites.
I also sort stuff in my head. Letters, numbers, symbols... And I always try to make them odds, because I want them to "hinge" on the "center". I even have a personal ranking system for letters based on how "tidy" their sizes are. The letters a, b, c, d, e, g, h, k, n, o, p, q, s, u, v, x, y, z, ø and å are my favourites, and I dislike the letters f, t, r, I and J utterly. My second favourite "class" consists of A, B, C, D, E, F, G, H, K, L, N, O, P, Q, R, S, T, U, V, X, Y, Z, Æ, Ø, m, w, æ, and my second least favourite is M, W and Æ. I also hate duplicate letters and instances where the letter order breaks the consonant, vowel, consonant format, and I try to order them so that each side of the word has equal "weight". This makes the word "wotalyrem" a perfect word. Or I rank them with the consonant following a pattern of equal descending order: "Mawonutel". Also permissible would be "moti".
I also order all numbers up to try to make them into the numbers 6, 10, 15 or 21, or to become a number like 737, 757, 666, 69, the current year or any other "significant" number.
In addition, I order all patterns of symbols into circles, hexagons, lines or other shapes hinging around a central symbol.
Weird enough yet

?
I also pour milk over my ice cream.