My favorite palindrome but not so long:
Cigar? Toss it in a can. It is so tragic.
Long + makes sense:
Doc, note I dissent. A fast never prevents a fatness. I diet on cod.
Longer, sort of makes sense:
T. Eliot, top bard, notes putrid tang emanating, is sad. I'd assign it a name: 'Gnat dirt upset on drab pot toilet'.
Pure Length:
http://www.norvig.com/palindrome.html#pal