絵里絵, pronounced erie: a kanji palindrome. Other kanji palindromes that spring to mind are 日曜日 ("Sunday") and 一対一 ("one on one").

Then there are "radical palindromes", like 林 ("grove") or -- if you're writing from top to bottom -- 昌 ("clear", "shining"). And here's one that's two characters long: 明日 ("tomorrow").*

Of course, word and phrase palindromes aren't very exciting. Sentences are where it's at. The Japanese word for "palindrome" is 回文, kaibun, and googling that brings up a few sites, such as this one (scroll past the English puns), which even has moraic-palindrome tanka:

叫ぶとも　遠き五月雨　汝は知らじ　離なれた岬　音も飛ぶ今朝
さけぶとも　とおきさみだれ　なはしらじ　はなれたみさき　おともとぶけさ
sakebu tomo tooki samidare na wa shiraji hanareta misaki oto mo tobu kesa

oh, it will cry
the distant May rain
unknown to you
a cape far away
even sounds fly this morning

Note that:

• wa is considered ha (which is how it's written)
• Voiced morae are considered identical to their unvoiced equivalents (shi/ji, ta/da)