SO Input field widths
HTML
<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/css/bootstrap-combined.min.css">
<script src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.2.2/js/bootstrap.min.js"></script>
<div class="container">
<div class="row">
<div class="span6">
<form class="form-horizontal">
<div class="control-group">
<label class="control-label" for="inputEmail">Email</label>
<div class="controls">
<div class="input-prepend input-block-level">
<span class="add-on"><i class="icon-envelope"></i></span>
<input type="email" id="inputEmail" class="input-block-level" placeholder="Email">
</div>
</div>
</div>
<div class="control-group">
<label class="control-label" for="inputPassword">Password</label>
<div class="controls"><div class="input-prepend input-block-level">
<span class="add-on passwordAddon"><i class=""> </i></span>
<input type="password" id="inputPassword" class="input-block-level password password-With-Prepend" placeholder="Password">
</div>
</div>
</form>
<hr>
<hr>
<form class="form-horizontal">
<div class="control-group">
<label class="control-label" for="inputEmail">Email</label>
<div class="controls">
<div class="input-prepend input-block-level">
<span class="add-on"><i class="icon-envelope"></i></span>
<input type="email" id="inputEmail" class="input-block-level" placeholder="Email">
</div>
</div>
</div>
<div class="control-group">
<label class="control-label" for="inputPassword">Password</label>
<div class="controls"><div class="input-prepend input-block-level">
<span class="add-on"><i class=""> </i></span>
<input type="password" id="inputPassword" class="input-block-level passwordPrepend"...
CSS
.passwordAddon{
background-color:inherit !important;
border-right:none !important;
}
.password-With-Prepend{
border-left:none !important;
}