My List:

- Stripe [http://stripe.com] (for Payment Handling)

- Heroku [http://heroku.com] (for Deployment)

- Amazon RDS [http://aws.amazon.com/rds/] (for DB hosting)

- Linode [http://linode.com] (512 is fine) (for Development)

- Postmark App* [http://postmarkapp.com] (for handling mail)

- Basecamp [http://basecamp.com] (for Project Management)

- Chartbeat [http://chartbeat.com] (for Stats)

- Sentry [http://getsentry.com] (for Exception Handling)

- Github Micro [http://github.com] (for Versioning & Private Repositories)

* Postmark charges for credits, not time. Either way, they do give 49,000 free credits for bootstrapped startups.