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We report photometry of the cataclysmic variable VI159 Orionis for -400 hours over 168 nights during 1992-4. The long-term light curves show that this is a dwarf nova of the SU UMa class, with normal outbursts recurring on a mean period of 4.0 days, and superoutbursts recurring on a period of 47.6 days. These periods wander slightly, as is typical of the class. High-speed photometry at minimum light, far from superoutbursts, reveals a weak photometric signal at 89.83 ±0.10 min, which is presumably the underlying orbital period of the binary. During superoutburst, large-amplitude superhumps are observed with P=92.4 min. The superhumps appear very suddenly on the rising branch. In a few days they fade to a full amplitude of -0.1 mag and become more complex in wave form. However, they can be traced throughout the decline phase to quiescence, and even apparently succeed in enduring to the next normal eruption. In fact, we note the occasional existence of superhumps at essentially all phases of the eruption cycle-not merely in supermaxima, where they are very common and downright famous. The "positive" (.P>P orb ) superhumps resemble in detail the common superhumps seen in the best-known SU UMa stars, and can be reasonably interpreted as arising from an eccentric accretion disk with an advancing line of apsides. But additional subtle details are detected in VI159 Ori. In one superoutburst the frequencies of the high harmonics are slightly higher than expected, and in another they are far lower than expected. And on two occasions there appeared "negative" superhumps (P

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We report the results of long observing campaigns on two novalike variables: V442 Ophiuchi and RX J1643.7+3402. These stars have high-excitation spectra, complex line profiles signifying mass loss at particular orbital phases, and similar orbital periods (respectively 0.12433 and 0.12056 d). They are well-credentialed members of the SW Sex class of cataclysmic variables. Their light curves are also quite complex. V442 Oph shows periodic signals with periods of 0.12090(8) and 4.37(15) days, and RX J1643.7+3402 shows similar signals at 0.11696(8) d and 4.05(12) d. We interpret these short and long periods respectively as a "negative superhump" and the wobble period of the accretion disk. The superhump could then possibly arise from the heating of the secondary (and structures fixed in the orbital frame) by inner-disk radiation, which reaches the secondary relatively unimpeded since the disk is not coplanar.At higher frequencies, both stars show another type of variability: quasi-periodic oscillations (QPOs) with a period near 1000 seconds. Underlying these strong signals of low stability may be weak signals of higher stability. Similar QPOs, and negative superhumps, are quite common features in SW Sex stars. Both can in principle be explained by ascribing strong magnetism to the white dwarf member of the binary; and we suggest that SW Sex stars are borderline AM Herculis binaries, usually drowned by a high accretion rate. This would provide an ancestor channel for AM Hers, whose origin is still mysterious.