CDKeys has 1-Year PlayStation Plus Membership (Digital Code) on sale for $29.89. (Verification after purchase may be required for this item)
eBay has the PlayStation plus membership 1 year subscription for $30.99 down from the original price of $59.99, ships for free via the neogames eBay merchant.
CDKeys has digital downloads of 1yr Sony PlayStation Plus Memberships on sale today for $29.39.
CDKeys has 1-Year Sony PlayStation Plus Membership (Digital Delivery) on sale for $35.49
This is only works for US accounts.