I have noticed that the 1998 philadelphia souvenir mint sets are selling as high as 800 dollars and the same coins in the normal mint set sell for around 10 and the brass mint medallion by itself sells next to nothing but in the souvenir together they sell for a small fortune, do you know of any of other examples where the packaging makes all the difference?
There are some Morgan Dollars which sell for a big premium if they are in a GSA holder with the box and papers. 1878-S is a common date, but if it's in a GSA holder, the Grey Sheet says it's worth. $3,000 in MS-62 and $4,000 in MS-63. There are no prices quotes after that, which must mean it doesn't exist or it's too thinly traded to price. A regular 1878-S is worth $80 in MS-62 according to the Grey Sheet.
Another GSA dollar is an 1864 seated dollar in G-4 in a GSA softpack holder. I believe the last time it sold it went for $8,000. It was supposedly the only seated dollar in the GSA sale. (I say supposedly because I have seen an 1872 seated dollar in low grade in a softpack GSA holder)