Ubuntu: Accessing local machine from remote machine through a connection initiated by local machine

Question

The tools:

• Remote: Ubuntu Server 11.04 in Amazon EC2
• Local: Ubuntu Desktop 11.04

The uses:

1. To create a Local backup of all my Remote virtual machines
2. To create a simple personal webpage on a single Remote machine to view my Local store of 60GB of images & some other files.

The problems:

1. ISP has blocked literally all ports, (topping the fact the IP is dynamic) so SSH connection must be initiated from the Local machine.
2. The connection must remain persistent? Or auto connect at given times perhaps?

Issues:

• It is likely I'd have a super slow connection to view my local images,
  but want to give it a shot anyway.

My question(s):

• I can handle the backups ( how to perform the actual backups ). How would I create a connection initiated from the Local machine?
• Is it okay, to leave the connection persistent (would it skyrocket my amazon bill even if I don't access it via webfront often?)
• How will the Remote machine know where to find the Local files? (In the case of viewing images) as in where do I look?
• Is it possible, for say a Remote PHP script to have read access to Local files?

Previous Encounter:

• I have seen the first case done before. I had a friend run a cron locally to perform incremental backups on a remote machine. I just want to do this myself and extend it a little further to the backing up of multiple machines plus accessing of Local files via Remote. Just don't know how to.

Thanks for reading! And thank you in advance for your replies...