What does +iwx mean?
Every time I connect, I see this:
+++ YourNick set to mode +iwx * YourNick sets mode: +iwx
And other variations on the theme.
This is the default mode applied to every user on connect to the irc.mibbit.net network.
Other networks may have slightly different defaults.
User mode +i means that the channels you are in are "invisible" to other non-administrator users that issue the /whois YourNick command.
- If you issue the /whois YourNick command on yourself, you are always listed.
- If you and the other user are in the same channel, you are always listed.
- If you are in a different channel than the other user,
- and if the channel you are in is not channel mode +s then the other user can see that you are in that other channel.
- If the channel you are in has channel mode +s then the other user can not see that you are in that other channel.
- You can issue the command /mode #TheChannel and see if s is in the list. It is Case Sensitive.
- If you are an OP of that channel, you can issue the command /mode #TheChannel +s and set +s. It is Case Sensitive.
- If you wish to disable this privacy protection, issue the command /mode YourNick -i. We don't recommend that you disable it, however.
User mode +w means that you can see network status messages called wallops. These are messages that the system and/or staff (Opers) considers important, such as a pending service downtime.
- To disable this notification, issue the command /mode YourNick -w.
User mode +x means that your IP/Host address is masked so that other users can not get your full IP/Host. This is also called a cloak.
- If you issue the /whois YourNick command on yourself, your IP/Host is always visible.
- For IP addresses, this is shown as (for example) "287AB38E.50E33866.F91BE320.IP". This is a hash generated by our IRCd, and no user can decode it.
- For Host names, this is shown as (for example) "mib-11DE075.hst16.fg.comcast.net". This is a hash generated by our IRCd, and no user can decode it.
- If you really want to turn off this privacy protection, you would issue the command /mode YourNick -x.
UnrealIRCD User and Channel modes 
UnrealIRCD User and Oper commands