How to instantly give people a pre-filled wallet to introduce them to Bitcoin? As a Bitcoin evangelist I like to introduce Bitcoin to my friends, and if possible even get them involved by having them own a few coins themselves.
The settlement of a personal debt through Bitcoin would be the perfect excuse to give someone their first coins. Who hasn't balanced expenses with their friends after a night on the town? Why not gain some new Bitcoin users in the process!
So, is there a way to securely set someone up with a new wallet and transfer some BTC to that wallet at the same time, without requiring any action from the receiving party?Ideally, the BTC.USD exchange rate is taken into account because such debts are unlikely to be denominated in BTC already.
Imagine the following conversation taking place:

Alice: I've paid the restaurant $100. So Bob, you now owe me $50.
Bob: Is it OK if I pay in Bitcoins?
Alice: Sure, but how does that work?
Bob: Don't worry, I'll just [PERFORM_MAGIC] so you'll have the equivalent amount of BTC in a brand new wallet straight away.

I can think of the following (slow, complex, frustration-prone) process to substitute PERFORM_MAGIC with:

Bob emailing some custom instructions telling Alice to install a
Bitcoin client
Alice following these instructions and possibly
having problems with the process
Alice emailing Bob her receiving
address
Bob transferring the coins to Alice.

Is there a way that requires less interaction, preferably accessible from my phone?
I would suggest starting a wallet at My Wallet (blockchain.info). 


It's dead simple, all you have to provide is a password
You don't have to enter any personal info about the person that you want to give the wallet to.
As opposed to e.g. Instawallet your friend can change that password so that you no longer have access to the wallet.
It is "mobile friendly" so you can do it from your phone, as you requested
It has a sleek and professional look so it won't scare away new users