klepto is one hell of a rune. I take it on veigar for the early game bonuses.
My friend got mana potions.
Haven't seen those in a LOOOONG time
basically anything that can use spell blade well take klepto on [slayer-pantheon-thumbs]
Initially, I was saying that, too.
Then I tried it on
.
I dubbed it Klept'mo and lord is it fun.
You sacrifice some early-early game power for "virtual immunity from being put-behind."
It's a safe rune for "Are you being put into a bad match-up, but can still poke and harass? "
Also the power of it is you can hit 3 and a partial complete items when most are on 2 and a partial. And you could be slightly behind in score.
In the end, it's a long-term pay-off rune. You might have a bit of a slow start, but, man, do you get to go ham after poking a bit.
Klepto is so fun xD
The good use cases are up for debate, but I just enjoy it too much on certain champs to pass it up. All those actives make a really big difference in lane, and it gets the snowball going much much earlier (especially when combined with Future's Market + cookies + TP). You do give up a lot of damage for it, though.
I have not played since the new runes went live, but I plan to take it on my solo lane, I men all applications of 
Rolled Corki in ARAM, went Klepto free boots + stopwatch. Stopwatch after The Package is pretty epic. I might actually build Zhonya's on him someday.
What does kelpto do?
Can this work on an ADC like say.....Vayne?
In one game as a Support Ezreal I got three skill potions.....
*edit. I was a support ap ezreal and got
By 20 mins.......