"Un-redefining" Google Chrome's console Object

I believe you could possibly do this with an iframe inject and then copy the iframe's console object:

<script type="text/javascript">
console = {};
try {
    console.log('1');
} catch(e){
    alert('No console');
}
</script>
<iframe id="text"></iframe>
<script type="text/javascript">
console = window.frames[0].console;
try {
    console.log('test');
} catch(e){
    alert('No console');
}
</script>

http://jsfiddle.net/nmY6k/

Note, this is just a demonstration that the concept should work.

EDIT

With a pure JS iframe:

<script type="text/javascript">
console = {};
try {
    console.log('1');
} catch(e){
    alert('No console');
}
var iframe = document.createElement('iframe');
document.body.appendChild(iframe);
console = window.frames[0].console;
try {
    console.log('test');
} catch(e){
    alert('No console');
}
</script>

http://jsfiddle.net/nmY6k/1/

EDIT

And of course, if you need to remove the iframe element afterwards:

<script type="text/javascript">
console = {};
try {
    console.log('1');
} catch(e){
    alert('No console');
}
var iframe = document.createElement('iframe');
document.body.appendChild(iframe);
console = window.frames[0].console;
try {
    console.log('test');
} catch(e){
    alert('No console');
}
console.log(typeof window.frames);
document.body.removeChild(iframe);
console.log(typeof window.frames);
</script>

In Google Chrome, deleting the console object works:

<script>
window.console = {};
delete console;
console.log('still works');
</script>

However, this doesn't seem to work in Firefox 4. It's a start, though.

This seems to work:

iframe = document.createElement('iframe');
document.body.appendChild(iframe);
console = iframe.contentWindow.console;

However it looks like you cannot remove the iframe