How to make text input box to occupy all the remaining width within parent block?

Updated [Oct 2016]: Flexbox version…

form {
  display: flex;
}
form input[type="text"] {
  flex: 1;
}

<form>
  <label>Name</label>
  <input type="text" />
  <button>Submit</button>
</form>
<p>Lorem ipsum...</p>

Original answer [Apr 2011]: Table-less CSS version (of table behavior)…

<div id="parent">
    <div id="inner">
        <label>Name</label>
        <span><input id="text" type="text" /></span>
        <input id="submit" type="button" value="Submit" />
    </div>
    <p>some paragraph text</p>
</div>

CSS…

#inner {
    display: table;
    width: 100%;
}
label {
    display: table-cell;
}
span {
    display: table-cell;
    width: 100%;
    padding: 0px 10px;
}
#text {
    width: 100%;
}
#submit {
    display: table-cell;
}

Demo: http://jsfiddle.net/wdm954/626B2/4/