Mark and Spencer currently have 20% of Mens Wear (Prices as Marked)
Also stack with £5 off £35 (Applies to Price before discount)
ALso Free Delivery to AU (Save £15)
Can be stacked with the Groupon £5 for £10 Mark and Spencer Gift Certificate if you bought one.
Edit 1: In addition they also have 20% off school uniforms (Thanks to redlikeapple)
Edit 2: 10.8% cashback on qwibble (Thanks to Feverz and confirmed working by Sweet3st)
http://www.qwibble.com.au/marks-spencer
Fine Print
20% off men’s clothing, shoes, accessories, toiletries and selected Father’s day gifts. Applies online at marksandspencer.com only from 9am–11.59pm on 10 June 2013. See individual items for details. Offer excludes M&S Outlet online, luggage, gift cards and sale items. Subject to availability. Discount will be shown at checkout. Offer does not apply to delivery charges. Please check relevant delivery terms and conditions online. Any refunds will take into account the discount. Higher prices have applied for 28 days or more on all items save for: Suits, Blazers and Jackets and Made to Measure shirts which was at 20% off from 29th May to 6th June 2013.
and 20% off school uniforms