US Airways is offering a 100% bonus on purchased miles through September 30, 2012. With this promotion, you can buy 100,000 US Airways miles, more than enough for a Business Class ticket to North Asia or just enough for one to Europe, for only $1,881.25. That is a deal if you plan to go to Europe anytime soon and can find the award availability.
And then there is Delta’s offer. Delta is offering a 50% bonus on purchased SkyMiles. With this promotion, you’ll earn a bonus 1,000 SkyMiles for every 2,000 SkyMiles you purchase on purchases up to 60,000 SkyMiles. With this promotion, you can purchase up to 60,000 SkyMiles, which will net you a total of 90,000 SkyMiles for the price of $2,257. The bonus with this offer adds up to 90,000 SkyMiles, which is just shy of enough miles to redeem at the low level for a Business Class ticket to Europe.