Just signed up to Plusnet standard ADSL (unlimited) broadband.
Its Free for 12 months on a 12 month contract with £75 cash back (from Plus Net).
Quidco are offering £135 for Standalone ADSL packages on top of this.
You just pay line rental (£16.99/ mo) but i went for the line rental saver @ £185.88 up front.
So you get £210 cash back in total for your package which only costs £185.88 + £6.99 router P&P charge.
So... i have the equivalent of free line rental, free broadband, free router and £17.13 in my back pocket
Seems like a no-brainer!
------ UPDATE ------
Quidco Cashback has tracked @ £135.
------ UPDATE 2 ------
Get an extra £5.58 if you have a Santander 1-2-3 account and opt to pay the line rental saver by DD! - thanks ahotukdeal
*** 13.11 - Quidco Cashback - DECLINED ***
Quidco Cashback Declined