Unique Coupon Codes

We have a business requirement to be able to create a mass number of unique coupon codes (x10,000+). I know you can restrict a coupon code to a target group, but with this requirement our business would like to be able to hand out generated coupon codes  without having to define a target group, but would like the coupons to be unique per customer. Can any of you offer some insight on how this might be configured?

Thanks in advance,