These days most online shops offer the ability to use discount codes at checkout and get a price reduction anywhere from 5% to 50%. These codes are announced in various media (like podcast or blogs), but even if you don’t follow the particular program, it is rather easy to find them with a search engine.
Given these premises, sites like Discoount Codes UK are welcome. I didn’t use their services personally, but it is well organized with direct links from the discount code to the store where you can use it and good reputation on sites which track such things (MyWOT, Norton SafeWeb and SiteAdvisor). For added safety I would recommend entering the addresses of the shops manually, rather than using the provided links. So there you have it: discount codes at your finger tips with the possibility to get a couple of percents off. And even if some don’t work, you have nothing to loose by trying to use them. Again a word of caution, especially around holiday shopping: be cautious and either use big-brand shops (like Amazon) or thoroughly check out the given shop (using a search engine and searching for phrases like “[shopname] complaints”, “[shopname] problems”, “[shopname] fraud”, etc). Better safe than sorry!
Full disclosure: this is a paid review from ReviewMe. Under the terms of the understanding I was not obligated to skew my viewpoint in any way (ie. only post positive facts).