Get a 280mm MSI AIO liquid cooler for £50 (half-price)
280mm is my favourite AIO liquid cooler size - cheaper than 360mm coolers while offering better performance per square inch - you just need a case that can accommodate the slightly larger fans. Normally getting a good AiO of this size costs around £100 to £180, but right now Amazon is offering the MSI MAG CoreLiquid 280R for half price: just £50. That's an awesome value for a high-performance CPU cooler that even includes RGB lighting.