きごう 【ｋｉｇｏｕ】 gives you a huge list of things, including ∀ and ♪ and ★ and ◎ as well as many of the symbols found below
ほし 【ｈｏｓｈｉ】 gives you stars ★☆※＊
ひし　【ｈｉｓｈｉ】 gives you diamonds ◇◆
ろしあ 【ｒｏｓｈｉａ】 gives you Cyrillic
さんかく 【ｓａｎｋａｋｕ】 gives you triangles △▽▲▼∵∴
てん 【ｔｅｎ】 gives you dots and periods and stuff ・‥
けいせん 【ｋｅｉｓｅｎ】 gives you boxdrawing things ┤┫┰
ぎりしゃ 【ｇｉｒｉｓｈａ】 gives you Greek Letters εΩξ
Typing [ or (　gives you all sorts of brackets