I have always looked at January as post holiday spending hangover month....where sales typically drop. This is has been true for my Amazon account but my eBay account is busier than it has been in like the last 6 months.
This is largely thanks to swimsuits and running shoes. I bought a lot of swimsuits for $3.99 each (almost all plus size) and I have sold around 2 dozen since right before Christmas. They aren't huge sales but they are 300-400% profit. On average they have been selling for $15-20+shipping.
The other seller that is coming as a surprise is Nike Running Shoes. I have sold 4 pair in the last 2 days. I bought 30 or so pair from Sports Authority in June/July for $6.50 per pair but they have sat and sat. They have sold for $25-40 free shipping.
I am chalking this up to the 40% 3 week sale I had going on at my store. Now that the credit card is paid off, it is time to stockpile some cash (my roof is now leaking) and make some room for yard sale season!