Let's have a new summoner spell or two...

Here's some ideas:

1. .5 second stun, range of flash or exhaust (for interrupting people like katarina/nunu)
2. option to choose a passive ability (Extra ap/attack damage etc.)
3. a buff for an ally (attack speed, deal more dmg for a little while)
4. make an enemy weaker (armor/magic resist debuff)
5. for a certain time, leave behind a trail that increases ally's movespeed (similar to iron potion) Just some ideas... even if these aren't good, i still think its time to make a new summoner spell. Any ideas would be useful in the comments.