After most captcha systems have been cracked a new system may solve, at least for some time, the problem of
differentiating man from machine as captcha (Completely Automated Public Turing tests to tell Computers and Humans Apart) was ment to do.

It's not yet clear if someone has legal rights on the method described herein (as more than one entity claims to be the first to think of/implement it).

Read more: http://news.cnet.com/8301-17938_105-10204300-1.html

http://www.instructables.com/id/Master_a_perfect_inline_wire_splice_everytime/

Video instructions:

http://www.metacafe.com/watch/385232/how_to_make_a_cd_cover_using_a4_paper/

-The easiest way to kill an RFID, and be sure that it is dead, is to throw it in the microwave for 5 seconds. Doing this will literally melt the chip and antenna making it impossible for the chip to ever be read again. Unfortunately this method has a certain fire risk associated with it. Killing an RFID chip this way will also leave visible evidence that it has been tampered with, making it an unsuitable method for killing the RFID tag in passports. Doing this to a credit card will probably also screw with the magnetic strip on the back making it un-swipeable.

-The second, slightly more convert and less damaging, way to kill an RFID tag is by piercing the chip with a knife or other sharp object. This can only be done if you know exactly where the chip is located within the tag. This method also leaves visible evidence of intentional damage done to the chip, so it is unsuitable for passports.

-The third method is cutting the antenna very close to the chip. By doing this the chip will have no way of receiving electricity, or transmitting its signal back to the reader. This technique also leaves minimal signs of damage, so it would probably not be a good idea to use this on a passport.

-The last (and most covert) method for destroying a RFID tag is to hit it with a hammer. Just pick up any ordinary hammer and give the chip a few swift hard whacks. This will destroy the chip, and leave no evidence that the tag has been tampered with. This method is suitable for destroying the tags in passports, because there will be no proof that you intentionally destroyed the chip.

Source:
http://www.instructables.com/id/How-to-blockkill-RFID-chips

An IRC allows you to send a voucher abroad, for example if you send someone a letter and want them to reply to you, as if this option
didn't exist you would have to either send them money or find a way to get stamps at the remote destination so they can reply.
The IRC voucher can be then be converted to mail stamps for air way mail services.

Read more here:

Royal Mail (UK)
Israeli Postal Authority
Wikipedia

If traveling to a foreign country you can usually have mail saved at one of the city's central post office's.
Read more here:

Royal Mail (UK)
Israeli Postal Authority
Wikipedia

An ethernet loopback is used to... perform loopback tests - obviously...
Lets cut to the chase - you can create two types of loopbacks, most only require the basic type.

RJ-45 Pinouts for Ethernet:

Pin	Name	Description
1	TX_D1+	Tranceive data +
2	TX_D1-	Tranceive data -
3	RX_D2+	Receive data +
4	BI_D3+	Bi-directional Data+
5	BI_D3-	Bi-directional Data-
6	RX_D2-	Receive data -
7	BI_D4+	Bi-directional Data+
8	BI_D4-	Bi-directional Data-

We always look at the connector from the underside - connectors
away from us.

Basic loopback (shown below - image from Juniper):

1. Looking from the underside of the connector, CAT5 cable connects from bottom.
2. Connect a cable to pin 1 and 3.
3. Connect a cable to pin 2 and 6.
4. Crimp.

Full loopback (often needed for gigaports - image from I-Hacked)

1. Looking from the underside of the connector, CAT5 cable connects from bottom.
2. Connect a cable to pin 1 and 3.
3. Connect a cable to pin 2 and 6.
4. (So far - same as the basic loopback).
5. Connect a cable to pin 4 and 7.
6. Connect a cable to pin 5 and 8.
7. Crimp.

Crossed

When to use ? A crossover cable is used (generally) when connecting the same device type to one another, e.g. switch to switch/switch-hub/hub-hub (unless using the uplink port) / computer-computer / router lan-switch or hub, etc...
Many modern switch's, hub's and router's support automatic MDI/MDI-X (Medium Dependent Interface / Medium Dependent Interface crossed), In general computers and routers use MDI and Switchs and Hubs use MDIX.

Quick tip: When creating crossover/loopback you always cross the cables as follows:

Side A        Side B
1                   3
2                   6
3                   1
6                   2

Leaving the other cables to run without crossing them; an easy way to remember how to cross is 1,2,3,6 goes to 3,6,1,2 (one, two, three, six -> three, six, one, two)