Also don't for get that Unlimited is not really 'Unlimited' they apply a Fair Use Policy, which has no rules and they can interpret anyway they like. The Sky one is as follows :-
FAIR USAGE POLICY
If you subscribe to a Product that does not have a Usage Cap, our Fair Use Policy (“FUP”) will apply to you and anybody that you allow to use Sky Broadband. Why have a Fair Use Policy?
Sky is committed to ensuring that our systems and network (“Sky Network”) and Sky Broadband are fast, reliable and great value for all of our customers. Our FUP is designed to help us keep that promise to you.
The bandwidth that is available on our network is shared by all customers that are active on the network at a particular point in time.
So, Sky relies on our users being fair and considerate of others in their broadband usage. If one person takes up too much or all the bandwidth, this results in a loss of service quality and speed for other users, and in some cases where one customer’s usage is excessive in the extreme, this can have a long-lasting detrimental effect on the rest of our users and the Sky Network.
Am I going to be affected by the Fair Use Policy?
Our FUP normally has little or no effect on the average broadband user. For example, if you do not excessively use file sharing software (including peer-to-peer) or regularly download very large files, you will most probably never be affected by the policy.
However, if your use of Sky Broadband becomes consistently excessive and has an adverse impact on the Sky Network and/or other users, our FUP enables us to intervene.
How can I manage my usage?
There are a number of ways to manage your usage, however the most effective is to keep your use of file sharing software (including peer-to-peer) and uploading and downloading of very large files reasonable. You should also only the e-mail accounts for e-mail purposes and not, for example, for as a storage facility.
How will I know if my usage is excessive?
Our aim is to provide a fair broadband service to all our customers. Therefore, we think to impose an actual figure on what we consider to be “excessive” use is not necessarily helpful and may penalise users unfairly. What is deemed excessive will be determined by a number of factors including (but not limited to) the length of time which your excessive usage continues for, as well as the amount of bandwidth being used.
If, in our reasonable opinion, you have breached this FUP, we may immediately suspend the relevant email account or we may contact you by email to let you know that your usage is excessive and is affecting the Sky Network and/or other users.
If after we have sent you the first email your usage continues to be excessive, we will contact you again by email to ask you to reduce you usage. If after a reasonable period of time your usage still remains excessive then we may do one or more of the following things by notice in writing:
(a) impose a monthly usage cap on your use of Sky Broadband which you must not exceed;
(b) pair your use of Sky Broadband with other users in the same excessive usage category as you;
(c) charge you fair and reasonable costs for your usage (and any reasonable administration costs);
(d) suspend your use of Sky Broadband for the relevant month;
(e) end your Contract in accordance with Condition 11 of your Contract; or
(f) suspend some or all of your Email Tools.