Depends on what you mean by "basic web app". For example, the Erlang-based CMS Zotonic runs beautifully on a T1.micro, even with PostgreSQL and an Nginx proxy

Depends on what you mean by "basic web app". For example, the Erlang-based CMS Zotonic runs beautifully on a T1.micro, even with PostgreSQL and an Nginx proxy on the same box.