You can't say you're a man until you try a game with AP/AS Janna.
Runes : Phase Rush + Manaflowband + Celerity + Waterwalking / Cheapshot + Rentless Hunter
Build : Nashor's Tooth (Rush it) + Blue Gem/Red Smite + Guinsoo's Rageblade + Frozen Mallet + 5th slot open (For example : Ardent Censer or Hextech Gun)
Boots : Swiftness (Mercury situational)
Insane sustain, bit slow in early to clear (use the fast-lvl3-trick), good gank potential, insane chase potential, jungle invade harass after first item (can't fight but amazing harass).