This article collects great jQuery form plug-ins and shares them with you. You are welcome to recommend more and better plug-ins. 1-jQuery inline form validation
2-Uniform
3-Autotab
4-jquery Niceforms
5-jquery Form Validator
6-Toggle FormText plug-in
7-jQuery Field Plug-in
8-In-Field Labels jQuery Plugin
9-jQuery Comment Preview
10-Input Fields with Images
11-Pretty Comments
12-jQuery Highlight Plugin
13-Select Multiple Form Fields
14-Password Masking jquery plugin
15-jTip
16-Password Strength Indicator and Generator
17-Live validation
18-jQuery Autosave
19-jQuery Dropdown Checkbox
20-jQuery Ajax Form Builder
21-Perfect signin dropdown box likes Twitter with jQuery
22-Checking username availability with ajax using jQuery
23-jqTransform
24-Magicpreview plug-in
25-A Fancy AJAX Contact Form
26-AJAX Upload
27-Current Field Highlighting in Forms
(Source: Dream sky Source: 25 + jquery Form Plugins)