in an attempt to make sense of 4 gb of dl for 512k, i am thinking of dual ISP;

i own a small business and have 512k Cyberia at work, and at home i have the all famous Ogero 512k.

the concept is that as soon as my Ogero caps out, i would switch to Cyberia, or vice versa. it's also good in-case of redundancy, if ogero or cyberia goes out the other takes over. (it also does load-balancing, meaning it can use both isp's at the same time)

two ways of doing this
1. cheap way - buy a singe adsl router, configure it to cyberia settings (let's say i'm at home) and when ogero caps unplug/plug

2. not so cheap way
http://www.peplink.com/ the Balance 20/30 will set you around 300$

*here is my question*

does cyberia/ogero check from which phone number the connection is being established?

thanks
If you load balance you will have 2 IPs. In situations this can - in theory - cause problems, some websites might refuse the same session being initiated from 2 different IPs. One thing you could do is have a VPS and create 2 tunnels to the VPS, then there recombining then into one connection. This is called Inverse multiplexing:
http://en.wikipedia.org/wiki/Inverse_multiplexing
VPS servers monthly rental are quite cheap nowadays (starts $20). I am thinking of getting one for my hosting needs. If you're interested we can try to implement the system that I described on my VPS, in a way that will satisfy us both.

The advantages over peplink:
- You will have the total of bandwidth available at the same time (ie approx 512 + 512) on the same connection. I'm not sure how peplink does load balancing but I think they do it by distributing connections to the various IPs, which as I pointed out before can cause problems and also it means that you can't have more then 512 on one connection. The only way you could have more then 512 on a download is by doing simultaneous download of multiple file chunks in a download manager (what is called download accelerator).

What you need is a computer connected to both ADSL accounts, preferably running linux (I dont know if what I described is possible with windows). It will act as the router/gateway for your network.

Regarding your question, I think someone answered it in the past. I think you can connect your account from another phone line if you want. But I want someone to confirm that.
There is no really need to use VPS, i myself was using a load balanced connection.
It worked great in torrents conditions with top speeds of 240kb/s (2mbps connection) but only two max 110 kb/s normal http downloads.