Classic Zopmod - Normal quake, except:

Runes (artifacts) - 75 different runes (a few dumb, yes); server can disallow each rune, if wanted.

More weapons - secondary on orig weapons: lightning nails, nail traps (float and then spread), burst (of nails) gun, multirockets, and railgun (sorry, it's not pretty).

Freehand hookshot - a must for any mod (also can be set to be secondary weapon).

Item switching - when an item respawns, it may switch locations with another item in the level.

More teamplay options and support - perm teams (two or three only), team frag count, and, at end of level, list of teams with frags, in order.

More gameplay options, such as rocket-arena (all weapons, inf ammo, or one of either), and that most of these additions can be disabled.

Client administrating - players use can use impulses to change settings and some physics, such as gravity and maxspeed without being on the server comp.

Server can set more values such as ammo useage, refire rates, some rune effects values, and amounts of items. Even more stuff, such as: any level can be disabled, random level selection, effects such as: when the no exit option is set, players can exit after timelimit reached or players that reached fraglimit can exit, and loads of other little things.

ZTF - (unreleased) Basically CTF, except you only need to stay in a flag's (small) area to get points, one per second. Many ways to play:

Free for all (no team), one flag - everyone tries to get the flag, by end of level (fraglimit/timelimit), whoever has had it longest (shown by frags) wins.

Free for all, multiple flags (2-4) - more flags to try to get, however you can hold only one at a time. Kill the other flag bearers.

Two teams, one flag - One team defends the flag. Either play two games and teams switch offense/defense or defenders get points for kills- undecided.

Two teams, two flags - Almost like ctf...

Two teams, three flags - One team has two flags to keep track of, the other has only one. Teams should not be equal.

Two teams, four flags - Both teams have two flags each. Crazy.

Three teams, one flag - Defenders defend against two teams, however, the two other teams are also fighting each other for the flag.

Three teams, two flags - Two teams have flags, one extra team thrown into the mix.

Three teams, three flags - Crazy.

Three teams, four flags - One team has two flags, the other two has one each. Hope for unequal teams.

In addition, certain teams' flags, set by server, can be picked up by opponents and stay above them, as like CTF. Players can be set to spawn in spawnpoints, random items, or near their flag. Flags can be made to be set randomly in spawn points, in places preset by the mod (editable, if you know how), or a random player can set the flag (player does not know what flag is being set). Players choose teams before play; server can set so that teams cannot be lost (unless player disconnects).

Thanks to the programmers of Orange mod and especially Nick "Singe", the creator of The artifact mod.