with / without hidden fields — See related blog post

Input:      
Hidden:     
Checkbox:   
Radio:      radio1
            radio2
Select:     
            
            select1
            select2
            
Textarea:   
Submit:     

Form source:

Input:      <input type="text" name="input" value="">
Hidden:     <input type="hidden" name="hidden" value="">
Checkbox:   <input type="hidden" name="checkbox" value=""><input type="checkbox" name="checkbox">
Radio:      <input type="hidden" name="radio" value=""><input type="radio" name="radio" value="radio1">radio1
            <input type="radio" name="radio" value="radio2">radio2
Select:     <select name="select">
            <option value=""></option>
            <option value="select1">select1</option>
            <option value="select2">select2</option>
            </select>
Textarea:   <textarea name="textarea"></textarea>
Submit:     <input type="submit" name="submit" value="">