jazzigor

“price-calc” is a WordPress plug-in that shows a nice inter-active price calculator form on any post, page or widget content. Let your customers view automatic bids and cost estimates for your products and services. You can set up a set of product variations and freely define a price structure. 
Once configured, it’s as easy as placing the simple 
[price-calc] 
mark-up anywhere in your text. The user gets a nice interactive form to choose all the characteristics he needs. When he’s ready he can see the quote instantly on the screen, print it out or get it by email.
PLEASE NOTE: There will not be any further development of this software. It will be replaced by <a href="http://www.l90r.com/posts/jazzy-forms" rel="nofollow ugc">Jazzy Forms</a>.
Features are:
<ul>
<li>AJAX user-experience,</li>
<li>different options for each general product type,</li>
<li>a fully configurable price structure,</li>
<li>instant price calculations appears on screen while the user fills in the form,</li>
<li>displays a detailed cost estimate on screen,</li>
<li>optional printer-friendly window pop-up,</li>
<li>optional email delivery to customer and/or your company.</li>
<li>user-defined calculation formula with addition, multiplication and percentages</li>
<li>customizable quote structure with intermediate results</li>
</ul>
Requirements:
<ul>
<li>PHP 5.2 or greater</li>
<li>WP 2.8 or greater</li>
</ul>
More info at this <a href="http://www.thickthumb.com/open-source/price-calc/" rel="nofollow ugc">plugin’s homepage</a>

price-calc

"price-calc" is a WordPress plug-in that shows a nice inter-active price calculator for your product variations on any post or page.

matthias.s

The Date Calculator plugin has NOW three basic functions.
<ul>
<li>
<ol>
<li>It returns the current date via the shortcode [date_now] in posts, pages and also in Contact Form 7-forms.</li>
</ol>
</li>
<li>
<ol>
<li>It can calculate a date up [date_add] or down [date_sub] and returns it in posts, pages and also in Contact Form 7 forms.</li>
</ol>
</li>
<li>
<ol>
<li>It can say a special date [date_say] like <code>last monday</code> or <code>second friday of next month</code> and returns it in posts, pages and also in Contact Form 7 forms.</li>
</ol>
</li>
</ul>
NEW IN VERSION 1.2.0: Now it is also possible to determine the date format!!!
This plugin enable the shortcode-support within Contact Form 7-forms so that the Date Calculator-shortcodes can also be used there.

Date Calculator

Date Calculator returns the current date via shortcode and it can calculate it into an other and returns it in posts, pages and also in CF7-forms.

price-calc vs Date Calculator