Checkout the best two plugins to add 125×125 ad square to your wordpress blog’s sidebar
WP125
WP125 widget comes with the multi-widget support, so you can use the same widget again if you have more than 8 ads . better for affiliate programs and your own ads.

Features of WP125
- One or two column ad display,UP TO 8 AD support per widget.
- Show your ad in manual or random order
- Keep track of how-many timesyourad is clicked
- Just input how many days you wish the ad to run
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Ad Squares Widget
Ad Squares Widget is just another simple plugin for 125×125 ads , Ad Squares Widget is better if you are using third party ad networks like buysellads.com .

I found Ad Squares Widget is more easy to use than WP125 plugin. so I recommend Ad Squares Widget for new bloggers.
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I am using WP 125 plugin in my blog. Everything is fine except their click statistics. For me the actual number of clicks and that shown by WP 125 have big difference.
Nice! Thanks for this. WP125 and I, are not friends! I think they count “hits” and not “clicks” btw.
Ad squares is great. I’d not heard of this plugin before, but I totally agree that it’s so easy to use.