2 years ago, I was tired of reshuffling papers and made the move to go paperless. This means that almost all paper is somehow converted to a digital image and stored in Evernote and/or TheBrain.  I scan them using my flatbed document scanner or Scanner Pro on the iPhone.

Why did I go paperless?

1. It is cleaner and helped de-clutter my work area. 
2. It also makes information much easier to find year later when I actually need it (aka searchability).
3. Last but not least, is portability. My digital Evernote storage is available wherever whenever (on any device).

The one caveat to my all digital conversion is store receipts, where I keep them until the end of the warranty period. The province I live in (Quebec) has very pro-consumer laws, but even here, it is up to the retailer to decide if digitally copied receipts are acceptable for returns or refunds. I contacted the online customer service centers for about a dozen of the largest Canadian retailers and most confirmed that they require the original store receipt (even when the store receipt had a barcode which could be read from my digital scan). A few of the retailers said they had no corporate policies preventing use of digitally reproduced receipts but that their store associated ultimately had the last word.