Richard Sweeney

This plugin makes adding a PayPal button to your site or blog very easy. There is no complicated shortcut syntax to remember (or to teach a client).
You can select on which type of post (including custom post types) you’d like to display the button.
There is a settings page for default values (username, currency etc), which can be customized for individual posts. (This might come in for sites with multiple users).
Choose from four custom button themes (with custom button text): light, dark, blue and red. If you prefer, you can simply display a standard large or small PayPal button.
Your PayPal username is converted to HTML entities so it can’t (easily) be harvested for spam by species 8472, or any passing Sith lord. It’s not a foolproof method, but it helps.
This plugin is created for WordPress 3.x and supports ‘Buy Now’ and ‘Donation’ functionality.

Easy PayPal Custom Fields

Easily add a PayPal 'donate' or 'buy now' button to your site.

Seans0n

The WordPress PayPal Donations Plugin allows you to create a donations page or post where your readers can donate any amount they wish. Features include:
<ul>
<li>Specify the number of donations and/or links to show</li>
<li>Specify an expiry date whereby donations older than this date will not be shown</li>
<li>Offer the ability to supply a link back to their own site if the user donates more than a specified amount</li>
<li>Show a graph bar showing how much has been donated towards your supplied target figure</li>
<li>Multiple currencies supported</li>
</ul>
WordPress PayPal Donations Plugin uses IPN to ensure the values are correct and you can also chose to display your total donations to date.
Related Links:
<ul>
<li><a href="http://www.seanbluestone.com/wordpress-paypal-donations-plugin" rel="nofollow ugc">Plugin Homepage</a></li>
</ul>

WordPress PayPal Donation Plugin

The WordPress PayPal Donations Plugin allows you to create a donations page or post where your readers can donate any amount they wish.

Easy PayPal Custom Fields vs WordPress PayPal Donation Plugin