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The word 'redicous' may have originally appeared as a phonetic rendering of the word 'ridiculous' - this seems to be the sense in how it's used. However, the 'red' start as opposed to the 'rid' beginning of 'ridiculous' suggests this isn't the whole story, and 'redicous' tends to be used by a younger, trendier group of people than the more staid, spluttery 'ridiculous'. In fact, the element of something laughable in the older word seems to be missing in 'redicous,' replaced by a hint of anger.
From various websites:

'This war is getting redicous.'
'You can still buy it at auction, but with redicous price.'
'I have a redicous amount of computer games.'
by Merwoman November 30, 2009